metadata: authors: 0: author: Marcotte, John
1: author: Casterline, John B.
count: Egypt, Arab Republic of
docna: 0: docna: Interrelations among child mortality,
            breastfeeding, and fertility in Egypt, 1975-80
docty: Policy Research Working Paper
subtopic: Reproductive Health,Early Child and Children's Health,Nutrition,Family Planning Research,Law and Justice Institutions
teratopic: Gender
abstracts: cdata!: This report examines the relationship
            between reproductive behavior and child survival in Egypt.
            The relationship is of fundamental importance to an
            understanding of demographic dynamics and for the
            formulation of population policies. Using Egyptian data from
            1975-80, it was found that weaning children in infancy
            increases ths risk of death for children under five. Early
            weaning is responsible for up to 29 percent of Egyptian
            children's deaths. Children whose mothers become
            pregnant again are more likely to die if the pregnancy
            begins while the child is still an infant. Ending
            breastfeeding is responsible for up to 41 percent of
            pregnancies - 52 percent among women who do not use
            contraceptives. Breastfeeding lasts an average of 17 to 18
            months in Egypt, so policy probably should not encourage all
            women to breastfeed longer, but women who breastfeed for
            only short periods should probably be encouraged to
            breastfeed longer. Parents should be encouraged to be more
            careful about childcare and children's diet and hygiene
            after weaning. An important feature of this analysis is that
            fertility was examined simultaneously with child survival
            and breastfeeding, as three components of a system. The
            analysis involved regression models for the hazard, or risk,
            of three events occurring after a live birth: another
            pregnancy, weaning, or the death of the child.
geo_reg_key: 517202,119229,517191
repnme: repnme: Interrelations among child mortality,
            breastfeeding, and fertility in Egypt, 1975-80
display_title: Interrelations among child
            mortality, breastfeeding, and fertility in Egypt, 1975-80
listing_relative_url: /research/1990/08/700199/interrelations-among-child-mortality-breastfeeding-fertility-egypt-1975-80
topicv3: Infant and Child Mortality m1326544 1446,Breastfeeding m1326777 1442,Nutrition m1326779 644,Contraceptives m1327726 1453,Mortality m1504365 3661
publishtoextweb_dt: 2010-07-01T00:00:00Z
historic_topic: Gender
origu: Policy, Research & Ect Affairs
no_of_pages: 57
model_extractions: **| Pol!ey, R search, and External Affairs**

**Ppliton, Hoslth, and Nutrition**

<!-- Start of picture text --> WPS 478<br><!-- End of picture text -->

- This paper a product of the Population, Health, and Nutrition Division, Population and Human Resources Department-is part of a larger effort in PRE to examine family consequences of high fertility. Copies are available free from the World Bank, 1818 H Street NW, Washington DC 20433. Please contact Susan Cochrane, room S6-139, extension 33222 (52 pages, including tables). Using Egyptian data from 1975-80, Marcotte and more careful about childcare and children's diet Casterline found that weaning children in and hygiene after weaning. infancy inc.eases the risk of death for children under five. Early weaning is responsible for up Replacement behavior in response to to 29 percent of Egyntian children's deaths. children's death accounts for up to 18 percent of pregnancies. It is not actual mortality but Children whose mothers become pregnant perceptions of a child's chances for survival that again are more likely to die if the pregnancy drive fertility. As infant deaths become less begins while the child is still an infarl. Ending common, the proportion of replacement pregnanbreastfeeding is responsible for up to 41 percent cies should decline. of pregnancies -52 percent among women who do not use contraceptives. An important feature of this analysis was

Using Egyptian data from 1975-80, Marcotte and Casterline found that weaning children in infancy inc.eases the risk of death for children under five. Early weaning is responsible for up to 29 percent of Egyntian children's deaths.

An important feature of this analysis was that fertility (represented by pregnancy) was examined simultaneously with child survival and breastfeeding, as three components of a system. The analysis involved regression models for the hazard, or risk, of three events occurring after a live birth: another pregnancy, weaning, or the death of the child.

Breastfeeding lasts an average 17 to 18 months in Egypt, so policy should probably not encourage all women to breastfeed longer, but women who breastfeed for only short periods should probably be encouraged to breastfeed longer. And parents should be encouraged to be The PRE Working Paper Series disseminates the findings of work under way **in** the Bank's Policy, Research, and Extemal AffairsComplex. An objective ofthe series is to get these **findings** outquickly. even if presentations areless than fullypolished. The findings, interpretations, and conclusions in these papers do not necessarily represent official Bank policy.

Produced by the PRE Dissemination Center
# Interrelations Among Child Mortality, Breastfeeding, and Fertility in Egypt, 1975-80

by John Marcotte and John B. Casterline

# Table of Contents

|I.|Introduction|1|
|---|---|---|
|II.|Mechanisms Linking Fertility, Child Survival, and<br>Breastfeeding|5|
||A.<br>The three events<br>B. Mechanisms|5<br>8|
|III.|<br>Data and Estimation|13|
||A. The data|13|
||B. Estimation|17|
||C. Analytic approach|19|
|IV.|Results|22|
||A. Mortality|22|
||B. Next pregnancy|26|
||C. Weaning|28|
|V.|Summary and Concluding Remarks|29|
|Table|s|33|
|Refer|ences|41|
|Appen|dices|43|
# I. INTRODUCTION

This report examines the relationship between reproductive behavior and child survival in Egypt. The relationship is of fundamental importance to an understanding of demographic dynamics in Egypt and for the formulation of population policies.

Various facets of the fertility - mortality relationship have been central concerns of demographic theory and research for many decades. Classical - demographic transition theory, as formulated in the 1930s 1950s, posits a lagged response of fertility to mortality: mortality declines, themselves a conseauence of exogenous improvements in standards of living and public health services, prompt corresponding declines in fertility, in order to prevent sustained rapid population growth and the stresses it causes to families at.d larger social groups. A review of the empirical evidence in the mid-1970s concluded that neither aggregate-level nor micro-level responses of fertility to infant and child mortality of the magnitude implied by classical demographic transition theory could be detected in historical European and contemporary Third World data (Preston, 1978). A more recent detailed micro-level investigation with World Fertility Survey (WFS) data from 25 developing countries (not including Egypt) suggests a somewhat stronger fertility response; nevertheless, on average the estimated response is one-half a birth for each child death, i.e. far from full fertility corpensation for child deaths (Cochrane and Zachariah, 1984). The fertility response can consist of voluntary and involuntary components; the mechanisms that may operate at the micro-level will be described in more detail in section II of this report.

1
The impact of fertility on child st'rvival has been a topic of a substantial body of empirical research during the past decade. Micro-level studies, many of them u lizing WFS data, have examined the impact on child survival of maternal age, maternal parity, and the timing of preceding and subseqiuent pregnancies (eg. Winikoff, 1983; Cleland and Sather, 1984; Hobcraft, et al., 1985; Palloni and Millman, 1986). Each of these three aspects of reproduction - maternal age, parity, and interval lengths - have been demonstrated to influence the likelihood of a birth surviving infancy and early childhood, with the impact of preceding and subsequent pregnancy (or birth) intervals being particularly large.

Previous analyses of Egyptian data have considered the relationship between reproductive behavior and child survival. A set of analyses of the Egyptian Fertility Survey (1980) have examined the micro-level effects. With respect to the impact of child survival on fertility, Callum, Farid, and Moussa (1988) show that birth intervals following infant deaths are substantially shorter than intervals following births that survive infancy. In addition to involuntary biological effects, behavioral (eg. contraceptive use patterns) and attitudinal (eg. desire for additional births) responses to infant and child mortality are both evident. With respect to the impact of fertility on child survival, maternal age, parity, and the length of the preceding birth interval have statistically significant and large net effects on infant mortality: births to wome- under age 20 or over age 39, births of parity seven and greater, and births following a preceding birth by less than 24 months are all distinctly disadvantaged (Eid and Casterline, 1988). Parity and length of the preceding birth interval, but not maternal age, also influence survival between age 1 and 5. A more detailed study of the birth spacing effect demonstrates a significant 2
net effect of the preceding and the succeeding interval (Callum and Cleland, 1988).

In this report, we consider again the micro-level relationship between reproductive behavior and child survival in Egypt, drawing once again on the rich set of information provided by the Egyptian Fertility Survey of 1980. The analysis we carry out is distinguished from previous analyses in the following respects.

First, we introduce breastfeeding behavior (specifically, the act of weaning) as a major component of reproductive behavior that influences both the survival of the child and the timing of the next conception. Especially in populations in which there is little regulation of marital fertility through contraception, breastfe.ding is a key variable for understanding the relationship between fertility and mortality. Palloni and Millman (1986) and Retherford et al. (1989) have investigared the contribution of breastfeeding to the estimated effect of birth spacing on child survival. In the former study, based on data from Latin America (where weaning occurs relatively early and contraceptive prevalence is relatively high), the contribution appears to be minor; in the latter study, based on data from Nepal (where the average breastfeeding duration is relatively long and contraception is virtually absent), breastfeeding appears to be the chief factor mediating the effect of birth spacing on child survival.

Second, we model fertility, child survival, and breastfeeding as a microlevel system. The estimation approach we adopt permics a full set of 3
effects to operate simultaneously. In this respect, the estimation approach a, ords with our conceptualization of the micro-level system, which acknowledges a host of reciprocal effects linking fertility, child survival, and breastfeeding (Cochrane and Zachariah, 1984).

The remainder of the report is organized as follows. In section II, we review the hypothesized mechanisms linking fertility, child survival, and breastfeeding at the micro-level. Section III describes the estimation approach and the data employed in the analysis. Results are presented in section IV. Four appendices attached to the main body of the report provide more detail about the statistical models, the data, and the results.

4
# 1I. MECHANISMS LINKING rERTILITY, CHILD SURVIVAL, AND BREASTFEEDING

# A. The three events

As indicated above, there are both macro- and micro-level facets to the relationship between reproductive behavior and mortality. At the micro-level, one can choose between women and births (or pregnancies) as units of analysis. It is natural to choose births as the unit of analysis, as many of the dynamics of interest refer to births (eg. survival, breastfeeding) or to intervals between births (time to next conception, contraceptive use). On theoretical grounds, however, it is essential to retain some connection to the woman (or couple) as the fundamental decision-maker. For example, the deleterious impact on child survival of intense fertility (large numbers of pregnancies, closelyspaced pregnancies, or births at very young ages) may persist over many births; and deliberate responses to child loss may persist over long stretches of a reproductive career. In this analysis, births are chosen as the- unit of analysis. Features of the past reproductive career of the woman (p_ .ty, length of the previous interval, age at the birth) are incorporated as covariates, but their estimated effects are given minimal attention here, as these have been analyzed in detail elsewhere (see discussion in section I). Instead, the interrelations between fertility, child survival, and breastfeeding are examined on a birth-by-birth (or interval-by-interval) basis. To the extent that relationships among these three variables exist that are only expressed over the long-term reproductive career, this analysis offers an incomplete portrait of the pertinent relationships.

**5**
Consider the fertility-mortality-breastfeeding system as consisting of the relationships among three events that may follow a live birth: the termination of breastfeeding (i.e., the weaning of the child); the death of the child; the birth of the next child (Marcotte, 1988). Clearly the latter two events need not occur for every birth; indeed, death of the child is a relatively rare event in most human populations. Breastfeeding eventually ends for all children; but in those cases where the child is breastfed until death, death effectively censors breastfeeding and the child is never weaned. Any one of the three events may not have occurred as of the time of data collection, i.e. they may be censored by the interview. A final point is that, where the data allow, it is preferable to use the onset of the next pregnancy (live or non-live outcome) rather than the next live birth as the fertility event, as most of the hypothesized effects concern pregnancy. (That is, weaning and mortality responses to the next pregnancy can occur during the pregnancy, prior to the next live birth).

Hence, we have three events to model jointly: weaning, death, next pregnancy. These three events are the basic drivers of demographic change. Particularly in societies where deliberate contraceptive behavior is rare - a situation typifying much of Africa (North and sub-Saharan) - to a considerable extent population dynamics (size, rate of growth, age structure) can be accounted for by simple aggregation of the risk of these three events occurring (singly and jointly). The contraceptive prevalence rate in Egypt at the time of the Egyptian Fertility Survey (the data used in this study) was roughly sixteen per cent, rather high by African standards but still indicative of the largescale absence of modern contraceptive efforts.

6
As noted above, following a birth all three events can occur, or two of them can occur, or one, or none (since a death can preclude weaning). Due to censoring by the i.nterview, one or more of the events that will eventually occur may not be observad. The events can occur in any order, with the exception of weaning following death. We view the child as progressing through a series of states following its birth. For example, a few months after giving birth a woman may stop breastfeeding (i.e., the child enters the state of weaned); a few months later, she may become pregnant (i.e., the child enters the state of next pregnancy); and perhaps a few months later, the child may die (ie, the child enters the state of death). In this example, weaning is followed by next pregnancy which is followed by death; other sequences can easily be imagined.

In this analysis, we examine how the occurrence of one of the three events modifies the likelihood of the occurrence of each of the other two events. The occurrence of one event is hypothesized to shift (upward or downward) the hazard for each of the other two events. The method of estimation makes use of the precise dating (on a monthly basis) of each event, but the results are driven mainly by the ordering of the events. The estimation is robust to some imprecision in the dating of events so long as the ordering is accurate. In particular, accurate ordering of events is essential to the estimation of reciprocal effects, such as weaning on fertility and fertility on weaning. Disentanglement of the reciprocal effects is accomplished by assuming that chronological order implies causal order.

The approach mighe be criticized for not taking into account the timing of the events (i.e., months since the birth): it is plausible, for example, that early weaning (prior to age twelve months, for example) has different 7
implications for the risk of dying than late beaning. To allow for timing effects, we explicitly estisnate separate effects of early and late occurrence of events. (Overall effects are also presented.) Marcotte (1988) introduces the conceptual model and the estimation approach. The estimation approach is described in section III, with greater detail provided in Appendices A and B.

# B. Mechanisms

We consider five effects: weaning on child death and on next pregnancy; next pregnancy on child death and on weaning; and child death on next pregnancy. (Child death precludes weaning: an effect of child death on weaning is therefore ruled out.) Note that these five effects imply a number of indirect effects: weaning can affect child death through the next pregnancy; weaning can affect the next pregnancy through child death; and the next pregnancy can influence child death through weaning. An innovation in the analysis presented below is that indirect effects are explicitly estimated and, moreover, total effects are decomposed as sums of direct and indirect effects, thereby providing a more complete description of the processes at work. (The decomposition technique is specified in section III.) Let us briefly review the mechanisms underlying each of the five effects. Effects that operate directly and indirectly (through one of the other events) are both described.

8
next reu nc enacy weaning _child death _fIgure 1_

# (1) Weaning on child death [figure 11.

Direct: Cessation of breastfeeding, if not fully compensated **by** food substitutes, can result in poorer nutrition (caloric intake, nutritional balance). In addition, food substi!L:Les lack the antibodies provided by breastmilk, and unhygienic preparation can lead to infection. Indirect: Weaning can exercise an indirect influence on child death by raising the risk of the occurrence of the next pregnancy (see (2)), which is posited to have an effect on the risk of chill death (see (3)) even when breastfeeding duration is controlled.

<!-- Start of picture text --> weaning -<br><!-- End of picture text --> <!-- Start of picture text --> . child death<br>next prasnancy<br>figure 2<br><!-- End of picture text -->

# (2) Wearing on next pregnancy ffigure 21.

Direct. The dominan. mechanism underlying this effect is the suppressing effect of lactation on ovulation (through the maintenance of high levels of the hormone prolactin). Additional mechanisms: customs abo.zt sexual behavior during lactation can result in coital frequency increasing sharply after weaning, increasing the risk of a next pregnancy; customs about contraceptive practice, in contrast, can result in more 9
intense contraception after weaning,<sup>reducing the risk of a next</sup> pregnancy.

Indirect: We iing can influence the<sup>risk of the next pregnancy</sup> indirectly by affecting the risk of death (see<sup>(1)), which itself affects</sup> the risk of a next pregnancy (see (5)) The death<sup>of a child in less</sup> developed countries often prompts replacement<sup>fertility behaviors.</sup> weaning next preanancy )child death _figure 3_

# (3) Next pregnancy on child death [figure<sup>31.</sup>

Direct: A pregnancy competes with the child<sup>for maternal resources</sup> (nutrition, care). This competition begins prior to parturition and becomes more directly evident thereafter.

Indirect: The next pregnancy can exercise<sup>an indirect effect on</sup> child survival through an effect on weaning<sup>(see (4)) and weaning's</sup> subsequent effect on child death (see<sup>(1)).</sup> next pregnancy weaning _figure 4_

# (4) Next gregnancy on weaning ffigure<sup>41.</sup>

Direct: While lactation suppresses<sup>ovulation (the fundamental</sup> mechanism underlying effect (2)), once<sup>conception occurs prolactin levels</sup> drop and lactation must diminish.<sup>Physical exhaustion induced by the</sup> 10
pregnancy may also lead to substitution of other foods for breastmilk, since other foods can be prepared and given to the child by individuals other than the mother.

# child death

) next Dregnancv _figure 5_

# (5) Child death on next pregnancy [figure 51.

Direct: The direct effects of child death on the risk of a next pregnancy are due to behavioral responses to the death, such as changes in contraceptive practice and in coital frequency. These changes may be motivated by a conscious desire to replace the deceased child or to accelerate the arrival of the next child.

Indirect: The effect of death on the risk of the next pregnancy is typically assumed to operate primarily through the cessation of breastfeeding. However, in behavioral terms, child death does not cause weaning; rather, child death censors breastfeeding. Thus, we do not allow for an indirect effect of child death on next pregnancy through weaning. But since we estimate all five effects as components of one overall system, the effects of child death on next pregnancy are estimated allowing for weaning effects on next pregnancy.

Our discussion of the mechanisms underlying the five effects has implicitly assumed a natural fertility, as opposed to a controlled fertility, population. The distinction is most salient with reference to effects on the next pregnancy: weaning on next pregnancy (see (2)), and child death on next 11
pregnancy (see (5)). These two effects are the result, in part, of changes in coital frequency and in contraceptive behavior. These two mechanisms operate in both non-contracepting and contracepting populations but to a lesser extent in the latter. Nevertheless, almost certainly the effect of weaning on the risk of a next pregnancy is much more powerful where fertility is not regulated<sup>by</sup> contraception; indeed, in such settings it may be the chief determinant of the level of marital fertility (Bongaarts, 1983). To permit empirical examination of how fertility control conditions the strengths of relationships, we estimate effects on the next pregnancy (of weaning and of child death) separately<sup>for</sup> birth intervals (closed and open) in which the woman reported<sup>not using and</sup> using contraception. For completeness, we estimate all five effects for both types of intervals. On theoretical grounds, all five effects<sup>can occur under</sup> conditions of unregulated or regulated fertility.

12
# III. DATA AND ESTIMATION

# A. The data

The data are from the Egyptian Fertility<sup>Survey, conducted in 1980 as part</sup> of the World Fertility Survey programme<sup>and in collaboration</sup> with the World Bank. The executing agency for the<sup>survey was the Central Agency for Public</sup> Mobilisation and Statistics (CAPMAS). The<sup>principal findings of the survey are</sup> presented in the four-volume survey report<sup>(CAPMAS, 1983) and in a further</sup> volume of in-depth analyses (Hallouda, Farid,<sup>and Cochrane, 1988). The EFS</sup> documents that Egypt is characterized by relatively high infant and child mortality (the infant mortality rate is<sup>roughly 130 for the five years preceding</sup> the survey), high fertility (a TFR<sup>of 5.27 for the five years preceding the</sup> survey), and long durations of breastfeeding<sup>(an average age at weaning of 17</sup> months). About one-quarter (24%) of currently-married women of reproductive age reported using some method of contraception in the five years prior to the survey, with the contraceptive pill the most popular method. The percentage of contraceptive users in our sample (24%) is different<sup>than in the total sample</sup> (16%) because our sample contains births<sup>in the five years prior to survey while</sup> the percentage for the total sample is based<sup>on current status.</sup> A complete pregnancy history (live and<sup>non-live births) was obtained in</sup> the EFS. For each live birth, survival<sup>status at the survey was ascertained,</sup> and the age at death (in months) of those<sup>children who died. Duration of</sup> breastfeeding of the most recent two live births was<sup>also obtained. Thus, with</sup> the EFS data it is possible to determine,<sup>for recent births, the ages (in</sup> months) at death, weaning, and next<sup>pregnancy. (For all children, age at next</sup> pregnancy is calculated by subtracting nine months from the age at the birth of 13
the next child; if the next pregnancy<sup>terminates in a non-live-birth</sup> outcome, the reported gestational length is<sup>used in the calculation. For those children</sup> who die before their mothers become<sup>pregnant again, age at next pregnancy is the</sup> age that the child would have attained<sup>if he had survived.)</sup> Because the EFS histories are collected<sup>retrospectively</sup> and only from women aged 15-49 at the time of the survey,<sup>the sample for this analysis is</sup> restricted to last and next-to-last births occurring within five years (60 months) of the survey. The five-year constraint<sup>is imposed for three reasons.</sup> First, it mitigates selection problems that<sup>result from using retrospective</sup> reports from a sample of women with an<sup>upper age restriction (49 in this</sup> instance). As the time period from which<sup>births are drawn is extended</sup> backwards, the data represent a smaller and<sup>smaller fraction of women in the</sup> childbearing ages and thus the sample becomes<sup>selective of certain maternal</sup> characteristics. In the five years preceding<sup>the survey, only children born to</sup> women aged 50-54 at the time of the survey<sup>are omitted, a negligible loss. The</sup> second reason for the time period restriction<sup>is to maximize reliability. We</sup> assume that information about events<sup>closer to the survey is of higher quality</sup> (more complete coverage, more accurate<sup>dating). Thirdly, .he EFS contains</sup> breastfeeding information for the last two<sup>children only, hence the restriction</sup> of the sample to last and next-to-last births. The further back that the<sup>time</sup> period of observation is extended, the more<sup>selective last and next-to-last</sup> births become of all births in the period.<sup>Over three-fourths (78%) of the</sup> births occurring in the five years<sup>immediately</sup> prior to the survey are either last or next-to-last births. Clearly an observation period<sup>briefer than five</sup> years would further alleviate each of these<sup>three problems. But a shorter time</sup> period would lead to less precise estimates,<sup>due to a smaller number of</sup> 14
observations; it would also result in a higher proportion of events censored by the survey..

Note that because of restriction of the sample to births in the sixty months preceding the survey, the longest possible interval between birth and onset of next pregnancy is sixty months. In Egypt, as in other moderate and high fertility settings, the majority of parity progressions will occur long before sixty months (Hoberaft and McDonald, 1984). Furthermore, the causal factors of principal concern in this analysis, namely death and weaning, should have little influence on the risk of pregnancy after sixty months.

We impose several additional restrictions on the data, to control potentially confounding factors. Non-Muslim women are excluded, in an effort to eliminate unmeasured heterogeneity in post-partum practices (abstinence, child feeding). This restriction eliminates less than ten per cent of births occurring during the reference period. Multiple births are excluded because information on the breastfeeding of such births is known to be unreliable in many fertility surveys. This restriction affects about two per cent of births Finally, we control sexual exposure by excluding births to women with marital disruption prior to any one of the three events and women who report that their husband was abroad at the time of interview. Unmarried women and women separated from their spouses have very low risk of becoming pregnant. Few children are lost because of these restrictions. The sample for analysis consists of 7375 children.

To mitigate spurious relationships among child death, weaning and next pregnancy, a standard set of variables are included in all estimations as 15
controls. These variables are: parity, age of mother, length of preceding birth interval, sex of child, region (Lower and Upper), size of place of residence (Cairo and Alexandria, other urban places, rural), maternal and paternal literacy and schooling, and whether contraception is used in the interval following the birth. In selecting these variables, we draw on the extensive analysis of the EFS (analyses of fertility, child survival, and breastfeeding) that has already been completed (Hallouda, Farid, and Cochrane, 1988). (See Appendix Z for definition of the control variables.) 16
# B. Estimation

We use hazard model techniques to estimate effects. The hazard is the instantaneous rate of an event occurring at a particular time. Coefficients represent how much higher or lower, in relative terms, is the hazard for one group as compared with another group. Full information maximum likelihood is the method of estimation. We estimate all parameters in the three event system simultaneously. The likelihood is a combination of the survival distributions for the three events. To operationalize the model, we use two parametric survival distributions, the Weibull and log-logistic. Under the Weibull, the hazard of an event occurring must increase or decrease monotonically while under, the log-logistic the hazard increases to a maximum and then declines. The Weibull is well suited for mortality under age five where the hazard of death decreases with age, and for weaning where the hazard increases with age. The hazard of a next pregnancy occurring follows a roughly log-logistic pattern: the hazard is low in the months immediately following a birth, rises to a maximum in the period 10 to 36 months following a birth and then declines. The likelihood is a combination of pieces that represent progressions between events. While it is complex with a large number of terms, the likelihood is, nevertheless, well defined. Appendix A shows the probability distributions and the terms of the likelihood). With standard maximization techniques (the Levenberg-Marquardt method), we obtain parameter estimates.

The sequence of the occurrence of events is essential to the estimation of the system. Indeed, the accuracy of the sequence of events is more essential than the accuracy of the ages themselves: the estimation of progression effects 17
relies on sequer:e. It is on<sup>the basis of sequence that reciprocal effects are</sup> estimated. For example, the model<sup>contains parameters that represent both the</sup> impact of weaning on the hazard of<sup>next pregnancy and the onset of the next</sup> pregnancy on the hazard of weaning.<sup>The measurement of ages in the EFS no doubt</sup> contains inaccuracies. The most<sup>glaring evidence of this is the high degree of</sup> heaping on cercain ages (multiples<sup>of six months) evident in the information on</sup> age at death and age at weaning (Eid<sup>and Casterline, 1988; Akin,</sup><sup>_et al.,_</sup> 1988). The shifting of reported ages from<sup>true values to certain convenient values can</sup> reduce the reliability of the ordering<sup>of the three ages of interest.</sup> The reliance on the sequence of events<sup>has further implications. For</sup> state A to influence state B, state<sup>Amust occur first. When two events occur</sup> at the same age, effects of one event<sup>on the other are not plausible, even</sup> though both events occur. This<sup>point is especially pertinent to estimation of</sup> the relationship between death and weaning. When<sup>death occurs prior to weaning,</sup> retrospective survey data may show that death<sup>and weaning occur in the same</sup> month. In reality, death has censored<sup>weaning, and the child remains unweaned</sup> even though the child is dead.<sup>It is important to recognize that death can</sup> censor weaning; failure to recognize<sup>this fact can lead to estimation of effects</sup> of breastfeeding on mortality<sup>that are seriously upwardly-biased. The problem</sup> is potentially acute in Egypt: because<sup>of the long durations of nursing, a</sup> large proportion of infant deaths<sup>are likely to occur prior to weaning (i.e.,</sup> death curtails breastfeeding)<sup>The observed weaned children are, therefore,</sup> selected with respect to survival,<sup>so weaning will appear to reduce the risk of</sup> dying. To mitigate this selection<sup>problem, in this analysis the models for</sup> mortality contain a parameter for<sup>the equality of breastfeeding duration and age</sup> at death. In effect, those cases<sup>for which the two ages are equal have been</sup> 18
separated out and do not contribute to the estimation of the reciprocal relationship between weaning and death. That is when these two ages are equal, it is assumed that the child is not weaned. All mortality probability functions include this parameter, which acts as a selection control only and does not have a causal interpretation.

As an alternative to the parametric model employed in this analysis, one might choose a semi-parametric specification. The Cox proportional hazards model is well known in demographic research. In the EFS data, survival times are heavily tied (partially due to heaping), however, which makes the semiparametric model difficult to operationalize. Another limitation of the semiparametric model is that shifts in the hazard that are attributable to the occurrences of the other events (i.e. time dependent covariates) are computationally difficult to estimate. Even with the parametric approach adopted here, estimation is computationally intensive. A final reason for preferring a parametric specification is that the decomposition of effects into direct and indirect effects is more eapi.ly defined and computationally more straightforward.

# C. Analytic approach

Following the discussion in section II of this report, we present results for three samples of births: (1) all births; (2) births to mothers who do not practice contraception prior to the next birth; (3) and births to mothers who do practice contraception prior to the next birth. As argued in section II, we expect the strength of some of the effects to vary according to the presence or 19
absence of fertility regulation. The measure of contraceptive practice is crude, however. The data only indicate the presence or absence of contraception in the interval; no information is provided on the tirming of use. The crudeness of the measure is particularly a concern with respect to the "regulators", who probably differ substantially among themselves in their contraceptive practice. Undoubtedly, net effects of this variable reflect more than fertility regulation _per se;_ the variable possibly selects on access to health care and on infant feeding practices (intensity of breastfeedirng, supplemental feeding regime). Another selection problem is that women with longer birth intervals way become "regulators" simply because they have had more time to adopt the practice. Information on timing of contraceptive use would permit a more refined partitioning of the sample, but the EFS does not contain this information.

We convert model coefficients into relative risk and attributable risk estimates. The relative risk shows by how much the occurrence of one event multiplies the hazard of another event occurring. A relative risk of 1.00 indicates no effect. A relative risk greater than 1.00 indicates that the occurrence of one event elevates the hazard of another event; a relative risk less than 1.00 implies reduction in the hazard. While the relative risk is a standard measure of effect in ha.ard models, the attributable risk has greater policy value. The attributable risk represents the percentage of events for which a particular characteristic is responsible. Walter (1976) discusses the estimation and interpretation of the attri:.utable risk. For example, an attributable risk of 35.0 indicates that a particular characteristic accounts for thirty-five per cent of events. If the attributable risk for weaning with respect to child death were 35.0, then up to thirty-five per cent of child deaths occur because of weaning. The attributable risk is influenced both by 20
the relative risk and by **the** proportion of the population with a particular characteristic. Note 'chat the attributable risk represents a maximum attribution. Note further that, depending on the events under consideration, it may not be feasible to reduce the risk by the amount indicated by the attributable risk; for example, it is not feasible to eliminate the weaning of children in Egypt. Use of attributable risks for policy purposes must be done with care. (See Appendix B for further details on relative and attributable risks.) We decompose relative risks into direct and indirect components. The decomposition shows what per cent of the effect of a particular factor iE mediated through an intervening variable. The decomposition further clarifies the mechanisms operating in the system. As noted in section II, many of the effects of interest are hypothesized to exercise both direct and indirect effects. For example, weaning influences mortality directly and indirectly (through modifying the risk of next pregnancy). To our knowledge, the direct and indirect effects linking child death, weaning, and next pregnancy have not been presented elsewhere. (See Appendix B for further details.) 21
# IV. RESULTS

We have three events (death, next pregnancy,<sup>and weaning) and five effects</sup> (i.e. all possible effects except death on weaning,<sup>which we rule out</sup> definitionally) to consider. We organize the presentation of results in terms of outcomes, beginning with child death as an outcome,<sup>then considering next</sup> pregnancy, and finally weaning.

# A. Mortality

A.1 Effects of weaning on child death [see figure 1] Since the sample is restricted to children born within 60<sup>months (five</sup> years) of the survey, we can only examine child<sup>mortality prior to 60 months.</sup> We shall term this age range "early childhood"<sup>(note that infancy is included).</sup> It is during these ages that breastfeeding and fertility affect child survival. Net of the influences of next pregnancy of mother,<sup>age and the other control</sup> variables, the hazard of dying for weaned children<sup>is about twice the hazard for</sup> the unweaned (see table 1; relative risk of<sup>2.06). The lower bound of the 95</sup> per cent confidence region puts the relative<sup>risk at a little greater than 1.4</sup> while the upper bound places it just<sup>under 3.0. (The confidence intervals are</sup> asymmetrical because they are based on the<sup>logarithm of the relative risk; see</sup> Appendix B). Over 51 per cent of the sample<sup>had weaned by the time of the</sup> survey or prior to death. That per cent<sup>in combination</sup> with the relative risk produces an attributable risk of 35.22 (95<sup>% CI, 16.63-49.67), i.e.</sup> breastfeeding practices account for up to<sup>35 per cent of early childhood</sup> mortality (including infant mortality) in<sup>Egypt. The impact of weaning should</sup> 22
be lower, or even non-existent, for older children since ordinarily they do not rely mainly on mother's milk for proper nutrition and immunization. For - children weaned prior to twelve months, the relative risk is 4.29 (2.91 6.33), while for children weaned after twelve months, the relative risk drops to 1.95 - (1.23 3.09). Note that although the relative risk is higher for children weaned prior to twelve months, the attributable risk is lower because only 12.54 per cent of children have weaned by that age. Early weaning before the end of - infancy is responsible for up to 29.21 (17.84 39.01) per cent of child mortality. While comparing the births followed by contraception and those not followed by contraception, we note that the impact of weaning is greater for the unregulated but that the age pattern of effects (i.e. weaned at 12 months versus weaned at 12 months or older) is the same as for all births. Our explanation is that use of contraception probably selects on use of formal health care services, which itself should reduce the impact of weaning on survival.

Weaning can also influence child mortality by increasing the likelihood of the mother becoming pregnant again. The total relative risk consists of both direct and indirect components. The total effect of weaning on child death is 2.43 (see table 2) The direct component (discussed in the previous paragraph) constitutes 81.45 per cent of that total (in the log-scale; see Appendix B). In the unregulated fertility population, the direct component is somewhat smaller, 73.75 per cent. Breastfeeding is one of the primary inhibitors of pregnancy in the unregulated population, and thus a larger indirect effect is expected for these births. When weaning occurs relatively early (i.e. prior to twelve months), the direct share is 87.44 per cent for all children.

A.2 Effects of next pregnancy on child death [see figure 31 23
We next consider the impact of naxt pregnancy of the mother on the child's survival. Other studies have attempted to capture the same effect by estimating effects of the length of the subsequent (or following) birth interval; results have varied from setting to setting. (For Egyptian results, see Callum and Cleland, 1988). As noted in section III, we take all next pregnancies into account, whnetner or riot they eventuate in a Live birth; the event of interest is conception (or the start of gestation). Once the mother becomes pregnant again, - the hazard of the child dying increases by a factor of 1.88 (1.46 2.43) as compared to the hazard for children whose mother is not pregnant, net of the influences of weaning, age and the other control variables (see table 3). The pregnancy must have begun at least one monch prior to either the death of the child or the survey if the child did not die. If the pregnancy started after the death of the child, it could not have produced a change in the risk of - mortality. Next pregnancy is responsible for up to 26.72 (15.30 36.61) per cent of child mortality (attributable risk) . As in the case of weaning, the effect is larger when the mother becomes pregnant again during infancy, as opposed to when the child is twelve months or older. Note that a conception within twelve months of live birth represents rapidly-paced fertility. Such - rapidly-paced fertility accounts for 22.20 (15.14 28.67) of child mortality (attributable risk). After the child achieves age twelve months, the impact of next pregnancy on the risk of dying largely disappears, a plausible result. One does not expect all subsequent fertility to be significantly disadvantageous for survival of an earlier child. The estimated effect is only slightly higher for the unregulated fertility population.

24
In addition to its direct impact, next pregnancy<sup>can also influence child</sup> mortality indirectly by inducing weaning. Over a<sup>quarter of the total effect of</sup> next pregnancy on child survival chances is transmitted<sup>through stoppage of</sup> breastfeeding (see table 4). When mothers become<sup>prcgnant again less than</sup> twelve months after the birth of the child under<sup>consideration,</sup> the indirect share drops substantially, due primarily to an increase in the direct effect relative risk. After twelve months, only the<sup>indirectcomponent</sup> shows significant impact.

25
# B. Next pregnancy

# **B.1** Effects of weaning on next pregnancy [see figure **21**

Breastfeeding has well established health effects, but it also helps to regulate fertility by suppressing ovulation. For all children, the hazard that - their mother will become pregnant again if they have been weaned is 3.02 (2.60 3.50) times the hazard if they have not weaned; this effect is net of child death, age and the other control variables (see table 5). Weaning is - responsible for up to 41.08 (35.38 46.28) per cent of mothers becoming pregnant again (attributable risk).

It is with respect to this effect that we expect the greatest differences between the unregulated and regulated fertility population, because in most natural fertility populations breastfeeding is the primary inhibitor of becoming pregnant again (Bongaarts, 1983). Conforming to these expectations, the - relative risk for the unregulated is 5.21 (4.04 6.71), while for the regulated - - it is 1.94 (1.59 2.37). Weaning accounts for up to 52.07 (43.45 59.38) per cent of next pregnancies for mothers who do not use contraception following the - birth, while it is responsible for up to 31.97 (22.31 40.43) per cent of next pregnancies for mothers who do practice contraception (attributable risks). Relative risk estimates do not vary significantly by age of weaning.

Weaning can also boost the hazard of next pregnancy indirectly by increasing the chances of child death, which in turn spurs fertility through a variety of behavioral mechanisms, including deliberate efforts to replace the 26
deceased child. In Egypt virtually all of the of impact of weaning on next pregnancy is direct, however (see table 6).

# B.2 Effects of child death on next pregnancy [see figure 5]

We consider next the effect of child death on the risk of next pregnancy. While the other relationships in our system are primarily biologically-based, this effect is behavioral. Keep in mind that, as the micro-level system is defined for this analysis, child death does not cause weaning (rather, it censors it), and thus an indirect effect of death on next pregnancy through weaning is ruled out. The direct effect of child death on the risk of next pregnancy is usually termed "replacement": deliberate efforts, through changes in coital frequency or in contraceptive behavior, to increase the probability of another conception.

Net of weaning and the other control variables, the hazard of next - pregnancy after child death is 3.22 (2.73 3.81) times the hazard of next pregnancy without a child death (see table 7). The share of next pregnancies - attributable to child deaths is up to 18.16 (14.32 21.83) per cent. The relationship between child death and next pregnancy does not vary significantly by age or by fertility control practice.

27
# C. Weaning

# Effects of next pregnancy on veaning [see figure 4]

Finally, we turn to effects on the risk of weaning. In the previous two sections, we have summarized the evid-nice from the EFS that weaning boosts the hazards both of child death and of next pregnancy. Next pregnancy, in turn, can also increase the chances of weaning by suppressing the production of mother's - milk. Children of pregnant mothers are 2.92 (2.72 3.14) times more likely to wean than children of non-pregnant mothers, net of the control variables (see - table 8). Next pregnancy accounts for up to 24.96 (22.68 27.18) per cent of child weanings (attributable risk). For the unregulated population, the influence of next pregnancy is greater; the relative risk is 3.24 (2.96 - 3.55). - In that population, next pregnancy is responsible for up to 28.27 (25.24 31.18) per cent of child weanings. In the regulated population, next pregnancy - accounts for 16.97 (13.30 20.49) per cent of weanings. In the unregulated population but not among the contraceptive, the impact of next pregnancy on weaning changes significantly with age. Women who do not practice contraception tend to breastfeed longer; the onset of the next pregnancy curtails prolonged nursing.

28
# V. SUMMARY AND CONCLUDING REMARKS

Reproductive behavior and child survival are related to each other through a complex set of mechanisms that operate at both the micro- and the macro-level. This analysis has examined the micro-level relationships between fertility and child survival, with explicit attention to the role of breastfeeding.

Breastfeeding has direct effects on both fertility and child survival; it also mediates the association between the two. In populations where use of modern - contraceptive techniques is at low levels such as Egypt at the time of the 1980 EFS - breastfeeding is perhaps the single most important proximate determinant of fertility and child survival.

An important feature of the analysis contained in this report is that fertility (represented in this report by pregnancy), child survival, and breastfeeding are examined simultaneously as components of a micro-level system.

The analysis consists of regression models for the hazard, or risk, of three events occurring subsequent to a live birth: anothar pregnancy, weaning of the child, and death of the child. The important results, in brief, are as follows: Weaning prior to the end of infancy increases the risk of death for children under age 5 years. Such early weaning is responsible for up to 29 per cant of child deaths in Egypt. About 18 per cent of the effect of breastfeeding on child mortality is related to an increased risk of pregnancy. Children whose mothers become pregnant again are more likely to d'e if the pregnancy begins while the child is still in infancy. Such fast paced fertility accounts for up to 22 per cent of child deaths. About 26 per cent of the impact of pregnancy on child mortality is indirect by increasing the risk of weaning.

After children wean, their mothers experience an increased risk of pregnancy. Cessation of breastfeeding practices is responsible for up to 41 per cent of pregnancies. Among women that do not use contraceptives, that figure rises to 52 per cent. Less than 2 per cent of the effect of breastfeeding on fertility acts indirectly through child mortality. Replacement behavior in response to deaths of children accounts for up to 18 percent of pregnancies.

29
When mothers become pregnant again, the chances that they will wean their children increase. Pregnancy is responsible for up to 24 per cent of the weanings in Egypt.

From a policy standpoint, several ef the results merit further discussion. Weaning shows substantial impact on child survival. Given the relatively long average breastfeeding durations (17-18) months in Egypt, it does not seem reasonable to conclude from these results that Egyptian women should be encouraged to breastfeed their children longer. It "ould be noted that the relative risk of death once a child is weaned is much higher if weaning occurs during infancy; those women who do breastfeed for rather short durations, for whatever reason, probably should be encouraged to breastfeed longer. But the important conclusion to be derived from this result is that weaning can be traumatic for the child, and therefore great care must be taken with respect to diet, hygiene and child care in the period immediately following cessation of breastfeeding.

The overall impact of chikld mortality on fertility as measured by the attributable risk is lower than expected if high mortality is in fact a primary determinant of high fertility. Mortality does have an effect, but even in a high infant mortality country such as Egypt, infant deaths are still relatively rare events. For the most part, however, it is not actual mortality but perceptions of child survival chances that drive fertility.

Many analyses of this type distinguish between "biological" and "behavioral" relationships. We have avoided this distinction, because we find it difficult to fit the relationships under examination into this classification. A more useful distinction is between deliberate and nondeliberate behaviors (eg. pregnancies that are deliberate to replace a child who died and conceptions that are non-deliberate because of termination of the anovulatory effects of lactation). Motive can not usually be imputed directly 30
from observed behavior since duration of breastfeeding is a function of biological, social and cultural variables, and these variables often overlap in their respective impacts.

For these reasons, we prefer to speak about distinct measurable behaviors rather than classifications that require assumptions about unmeasured attitudes and behaviors. Nevertheless, it is of some importance to recognize that in Egypt in the 1970s there is little evidence of deliberate efforts to act on levels of fertility; the measured levels of contraceptive practice are one of the indicators. There is also little evidence that decisions about how long to breastfeed were motivated mainly by child health or fertility considerations, although one can assume that concerns about child health were a factor. We do estimate a substantial effect of child death on the risk of a next pregnancy (net of weaning, i.e. controlling for breastfeeding), however. This suggests deliberate efforts to replace dead children - "replacement effects" - that are commonly termed "behavioral".

The powerful effects that emerge from this analysis are, for the most part, effects that are most reasonably assumed to be non-deliberate: weaning on the risk of child death; weaning on the risk of becoming pregnant again; child death on the risk of becoming pregnant again; pregnancy on weaning. At the same time, most of these relationships are susceptible to modification through deliberate public health policies and through individual behavioral changes. Note that some of these changes would impact the attributable risk but not the relative risk. For example, the relative risk of a pregnancy following a death may not change; but as child deaths become less common, this relationship accoun<sup>t</sup> s for fewer pregnancies. That is, it is essential to consider both the magnitude of effects and the relative size of the population at risk. Both are 31
susceptible to macro-policy interventions and intentional individual efforts<sup>to</sup> change behavior.

32
# TABLE 1 EGYPT 1975-80 THE DIRECT IMPACT OF WEANING ON CHILD MORTALITY (before age 60 months)

% per cent weaned (ceased breastfeeding prior to child death) RR relative risk of child death (weaned / not weaned) AR attributable risk of child death

-------------FERTILITY CONTROL--------------ALL (N-7375 children) NO (N-4714 children) YES (N-2661 children) EST. (95 % CI) EST. (95 % CI) EST. (95 % CI) WEANED at any age % 51.19 (50.05 - 52.33) 44.63 (43.21 - 46.05) 62.80 (60.96 - 64.63) RR 2.06 ( 1.43 - 2.98) 2.21 ( 1.34 - 3.65) * AR 35.22 (16.63 - 49.67) 35.10 (10.51 - 52.94) * WEANED before 12 months % 12.54 (11.79 - 13.30) 9.61 ( 8.77 - 10.45) 17.74 (16.29 - 19.19) RR 4.29 ( 2.91 - 6.33) 5.13 ( .3.02 - 8.71) 3.35 ( 1.78 - 6.30) AR 29.21 (17.84 - 39.01) 28.39 (13.52 - 40.71) 29.41 ( 7.91 - 45.89) WEANED at 12 months or later % 57.25 (55.88 - 58.63) 57.39 (55.58 - 59.19) 57.07 (54.95 - 59.18) RR 1.95 ( 1.23 - 3.09) 2.60 ( 1.44 - 4.68) * AR 35.17 ( 9.44 - 53.58) 47.81 (17.48 - 66.99) *

based on Weibull proportional hazards model controlling for: next pregnancy of mother, parity, age of mother, preceding birth interval length, sex, region, urban/rural residence, fertility control, education of mother, education of father based on data from the Egyptian Fertility Survey 1980 restrictions: children born within 60 months of survey to married women last two children only no multiple births no marital disruption prior to child death Muslim only note: some children still breastfeeding at survey (not weaned) some children breastfed until died (not weaned)

*-not statistically distinguishable

from 0.0 for per cent (%) and attributable risk (AR) and from 1.0 for relative risk (RR) 33
**TABLE 2 EGYPT 1975-80**

**DECOMPOSITION OF THE TOTAL IMPACT OF WEANING ON CHILD MORTALITY (before age 60 months)**

WEANED ceased breastfeeding prior to child death PREGNANT mother became pregnant after weaning and prior to child death RR relative risk of child death (weaned / not weaned)

-FERTILITY CONTROL-------ALL ln(RR) % NO ln(RR) & YES ln(RR) % WEANED RR at anyage TOTAL 2.43 100.00 i 2.93 100.00 **'1.09** 100.00 % DIRECT 2.06 81.45 % 2.21 73.75 % * INDIRECT 1.18 18.55 % 1.33 26.25 % 1.09 100.00 % (through pregnant) WEANED RR before 12 months TOTAL 5.29 100.00 % 6.94 100.00 % 3.87 100.00 % DIRECT 4.29 87.44 % 5.13 84.39 % 3.35 89.37 % INDIRECT 1.23 12.56 % 1.35 15.61 % 1.15 10.63 % (through pregnant) WEANED RR at 12 months or later TOTAL 1.95 100.00 % 2.60 100.00 % * DIRECT 1.95 100.00 % 2.60 100.00 % * INDIRECT * * * (through pregnant)

based on Weibull proportional hazards and log-logistic models controlling for: next pregnancy of mother, weaning, parity, age of mother, preceding birth interval length, sex, region, urban/rural residence, fertility control, education of mother, education of father indirect effects evaluated at mean age of pregnancy based on data from the Egyptian Fertility Survey 1980 restrictions: children born within 60 months of survey to married women last two children only no multiple births no marital disruption prior to child death Muslim only

*-not statistically distinguishbble from 1.0

34
**TABLE 3 EGYPT 1975-80 THE DIRECT IMPACT OF NEXT PREGNANCY ON**<sup>**CHILD MORTALITY (before age 60 months)**</sup>

% per cent pregnant (mother became pregnant<sup>prior to child death)</sup> RR relative risk of child death (pregnant /<sup>not pregnant)</sup> AR attributable risk of child death

-------------FERTILITY CONTROL--------------ALL (N-7375 children) NO (N-4714 children) YES (N-2661 children) EST. (95 % CI) EST. (95 % CI) EST. (95 % CI) PREGNANT at anY S % 41.30 (40.18 - 42.43) 38.27 (36.88 - 39.66) 46.67 (44.78 - 48.57) RR 1.88 ( 1.46 - 2.43) 2.08 ( 1.52 - 2.85) 1.74 ( 1.11 - 2.74) AR 26.72 (15.30 - 36.61) 29.29 (15.52 - 40.82) 25.74 ( 2.37 - 43.52) PREGNANT before 12 months % 13.45 (12.67 - 14.23) 13.47 (12.50 - 14.45) 13.42 (12.12 - 14.71) RR 3.12 ( 2.40 - 4.06) 3.34 ( 2.40 - 4.66) 2.67 ( 1.70 - 4.19) AR 22.20 (15.14 - 28.67) 23.99 (14.70 - 32.27) 18.31 ( 6.71 - 28.46) PREGNANT at 12 months or later % 41.26 (39.89 - 42.63) 40.63 (38.84 - 42.43) 42.12 (40.01 - 44.23) RR * * * AR * * *

based on Weibull proportional hazards model controlling for: weaning, parity, age of mother, preceding birth interval length, sex, region, urban/rural residence, fertility control, education of mother, education of father based on data from the Egyptian Fertility Survey 1980 restrictions: children born within 60 months of survey to<sup>married women</sup> last two children only no multiple births no marital disruption prior to child death Muslim only note: some mothers do not become pregnant by survey *-not statistically distinguishable from 0.0 for per cent (%) and attributable risk (AR) and from 1.0 for relative risk (RR) 35
# TABLE 4 EGYPT 1975-80

DECOMPOSITION OF THE TOTAL IMPACT OF NEXT<sup>PREGNANCY ON CHILD MORTALITY</sup> (before age 60 months) PREGNANT mother becamse pregnant prior to<sup>child death</sup> WEANED ceased breastfeeding after mother<sup>became pregnant</sup> and prior to child death RR relative risk of child death (pregnant /<sup>not pregnant)</sup>

**-** - FERTILITY CONTROLALL ln(RR) % NO ln(RR) % YES ln(RR) % REGNANLRR at any age TOTAL 2.34 100.00 % 2.61 100.00 % 1.74 100.00 % DIRECT 1.88 74.27 e 2.08 76.36 % 1.74 100.00 % INDIRECT 1.25 25.73 % 1.25 23.64 % * (through weaned) PREGNANT RR before 12 months TOTAL 3.71 100.00 % 3.80 100.00 % 3.10 100.00 % DIRECT 3.12 86.88 % 3.34 90.33 % 2.67 86.93 % INDIRECT 1.19 13.12 % 1.14 9.67 % 1.16 13.07 % (through weaned) PREGNANT RR at 12 months or later TOTAL 1.31 100.00 % 1.55 100.00 % * DIRECT * * * INDIRECT 1.31 100.00 % 1.55 100.00 % * (through weaned)

based on Weibull proportional hazards and log-logistic<sup>models</sup> controlling for: weaning, next pregnancy of<sup>mother,</sup> parity, age of mother, preceding birth<sup>interval length,</sup> sex, region, urban/rural residence, fertility<sup>control,</sup> education of mother, education of father indirect effects evaluated at mean age of<sup>weaning</sup> based on data from the Egyptian Fertility<sup>Survey 1980</sup> restrictions: children born within 60 months<sup>of survey to married women</sup> last two children only no multiple births no marital disrupcion prior to child<sup>death</sup> Muslim only

*-not statistically distinguishable from<sup>1.0</sup>

36
TABLE 5 EGYPT 1975-80 THE DIRECT IMPACT OF **VEANING** ON NEXT PREGNANCY OF<sup>MOTHER (before</sup><sup>**age**60 months)</sup> % per cent weaned (ceased breastfeeding prior to next pregnancy) RR relative risk of pregnancy of mother (weaned<sup>/not weaned)</sup> AR attributable risk of pregnancy of<sup>mother</sup>

-------------FERTILITY CONTROL--------------ALL (N-7375 children) NO (N-4714 children) YES (N-2661 children) EST. (95 % CI) EST. (95 % CI) EST. (95 % CI)

% 34.58 (33.49 - 35.66) 25.82 (24.57 - 27.07) 50.09 (48.19 - 51.99) RR 3.02 ( 2.60 - 3.50) 5.21 ( 4.04 - 6.71) 1.94 ( 1.59 - 2.37) AR 41.08 (35.38 - 46.28) 52.07 (43.45 - 59.38) 31.97 (22.31 - 40.43) WEANED before 12 months % 8.98 ( 8.32 - 9.63) 5.71 ( 5.04 - 6.37) 14.77 (13.42 - 16.12) RR 2.91 ( 2.43 - 3.47) 4.69 ( 3.43 - 6.42) 2.06 ( 1.63 - 2.60) AR 14.60 (11.04 - 18.02) 17.39 (11.20 - 23.14) 13.51 ( 7.89 - 18.79) WEANED at 12 months or later % 42.19 (40.74 - 43.64) 37.66 (35.77 - 39.56) 48.01 (45.80 - 50.22) RR 3.07 ( 2.48 - 3.79) 6.06 ( 4.04 - 9.10) 1.84 ( 1.41 - 2.41) AR 46.62 (38.15 - 53.93) 65.60 (52.60 - 75.04) 28.74 (15.52 - 39.90) WEANED before 12 months based on log-logistic model controlling for: child death, parity, age of mother, preceding birth interval<sup>length,</sup> sex, region, urban/rural residence, fertility<sup>control,</sup> education of mother, education of father based on data from the Egyptian Fertility Survey 1980 restrictions: children born within 60 months of survey to<sup>married women</sup> last two children only no multiple births no marital disruption prior to child death Muslim only note: some children still breastfeeding at survey (not weaned) some children breastfed until died (not weaned)

*-not statistically distinguishable from 0.0 for per cent (%) and attributable risk (AR) and from 1.0 for relative risk (RR)

37
TABLE 6 EGYPT 1975-80 DECONPOSITION OF THE TOTAL IMPACT OF WEANING ON NEXr PREGNANCY OF MOTHER (before **age** 60 months) WEANED ceased breastfeeding prior to next pregnancy of mother DEATH child death prior to next pregnancy of mother and after weaning RR relative risk of pregnancy of mother (weaned / not weaned)

--------FERTILITY CONTROL-

ALL ln(RR) % NO ln(RR) % YES ln(RR) % WEANED RR at any age TOTAL 3.07 100.00 % 5.28 100.00 % 1.94 100.00 % DIRECT 3.02 98.51 % 5.21 99.16 % 1.94 100.00 % INDILE:CT 1.02 1.49 % 1.01 0.84 % * (through child death) WEANED RR before 12 months TOTAL 3.00 100.00 % 4.81 100.00 % 2.18 100.00 % DIRECT 2.91 97.12 & 4.69 98.38 % 2.06 92.70 % INDIRECT 1.03 2.88 % 1.03 1.62 % 1.06 7.30 % (through child death) WEANED RR at 12 months or later TOTAL 3.07 100.00 % 6.06 100.00 % 1.84 100.00 % DIRECT 3.07 100.00 % 6.06 100.00 % 1.84 100.00 % INDIRECT * (through child death) based on Weibull proportional hazards a.id log-logistic models controlling for: child death, weaning, parity, age of mother, preceding birth interval length, sex, region, urban/rural residence, fertility control, education of mother, education of father indirect effects evaluated at mean age of childreal based on data from the Egyptian Fertility Survey 1980 restrictions: children born w<sup>4</sup> thin 60 months of survey to married women last two children only no multiple births no marital disruption prior to child death Muslim only

*-not statistically distinguishable from 1.0

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# TABLE 7 **EGYPT 1975-80 THE DIRECT IMPACT OF CHILD DEA'TH ON NEXT PREGNANCY OF MOTHER (before age 60 months)**

% per cent dead (child death prior to pregnancy of mother) RR relative risk of pregnancy of mother (child death / no child death) AR attributable risk of pregnancy of mother

-------------FERTILITY CONTROL--------------ALL (N-7375 children) NO (N-4714 children) YES (N-2661 children) EST (95 % CI) EST. (95 % CI) EST. (95 % CI)

CHILD DEATH at any age % 9.98 ( 9.30 - 10.66) 10.73 ( 9.85 - 11.62) 8.64 ( 7.57 - 9.71) RR 3.22 ( 2.73 - 3.81) 3.22 ( 2.62 - 3.95) 3.16 ( 2.34 - 4.26) AR 18.1C (14.32 - 21.83) 19.22 (14.28 - 23.88) 15.73 ( 9.49 - 21.54) CHILD DEATH before 12 months % 8.88 ( 8.23 - 9.53) 9.50 ( 8.67 - 10.34) 7.78 ( 6.76 - 8.80) RR 3.25 ( 2.74 - 3.85) 3.19 ( 2.59 - 3.92) 3.23 ( 2.39 - 4.36) AR 16.64 (13.03 - 20.11) 17.21 (12.62 - 21.56) 14.76 ( 8.82 - 20.31) CHILD DEATH at 12 months or later % 1.81 ( 1.42 - 2.20) 2.30 ( 1.72 - 2.89) 1.17 ( 0.70 - 1.65) 1KR * * * AR * * * based on log-logistic model controlling for: weaning, parity, age of mother, preceding birth interval length, sex, region, urban/rural residence, fertility control, education of mother, education of father based on data from the Egyptian Fertility Survey 1980 restrictions: children born within 60 months of survey to married women iast two children only no multiple births no marital disruption prior to child death Muslim only note: some children still alive at survey

*-not statistically distinguishable from 0.0 for per cent (%) and attributable risk (AR) and from 1.0 for relative risk (RR)

39
TABLE 8 EGYPT 1975-80 THE DIRECT IMPACT OF NEXT PREGNANCY ON **WEANING** (before age 60 months) % per cent pregnant (mother became pregnant prior to weaning) RR relative risk of weaning (pregnant / not pregnant) AR attributable risk of weaning

-------------FERTILITY CONTROL--------------ALL (N-7375 children) NO (N=4714 children) YES (N-2661 children) EST. (95 % CI) EST. (95 % CI) EST. (95 % CI)

PREGNANT at any age % 17.33 (16.46 - 18.19) 17.59 (16.50 - 18.67) 16.87 (15.45 - 18.30) RR 2.92 ( 2.72 - 3.14) 3.24 ( 2.96 - 3.55) 2.21 ( 1.94 - 2.52) AR 24.96 (22.68 - 27.18) 28.27 (25.24 - 31.18) 16.97 (13.30 - 20.49) PREGNANT before 12 months % 9.36 ( 8.69 - 10.02) 9.86 ( 9.01 - 10.71) 8.45 ( 7.40 - 9.51) RR 2.92 ( 2.71 - 3.15) 2.90 ( 2.63 - 3.20) 2.19 ( 1.88 - 2.54) AR 15.23 (13.49 - 16.93) 15.77 (13.44 - 18.04) 9.12 ( 6.59 - 11.59) PREGNANT at 12 months or later % 14.87 (13.77 - 15.98) 15.29 (13.85 - 16.74) 14.24 (12.51 - 15.97) RR 3.20 ( 2.87 - 3.58) 3.91 ( 3.43 - 4.47) 2.27 ( 1.82 - 2.82) AR 24.68 (21.31 - 27.90) 30.82 (26.37 - 35.01) 15.29 ( 9.82 - 20.43) based on Weibull proportional hazards model controlling for: parity, age of mother, preceding birth interval length, sex, region, urban/rural residence, fertility control, education of mother, education of father based on data from the Egyptian Fertility Survey 1980 restrictions: children born within 60 months of survey to married women last two children only no multiple births no marital disruption prior to child death Muslim only note: some mothers do not become pregnant by survey

*-not statistically distinguishable from 0.0 for per cent (%) and attributable risk (AR) and from 1.0 for relative risk (RR)

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