2 of transmission may, however, include ingestion of unpas- teurised milk and direct implantation through skin abrasion or the conjunctiva. Aerosolized tuberculosis particles with sizes ranging between 1 and 5 um are carried to the terminal air spaces of high-airﬂow areas, where multiplication of the tubercle occurs. Following phagocytosis by pulmonary ma- crophages, a granulomatous reaction may be initiated, in conjunction with the regional lymph nodes, thereby forming the Ghon’s focus. The bacilli remain in a state of dormancy within the Ghon’s focus, from where they may later become reactivated. 4. Tuberculosis in Pregnancy The wide array of opinion of Medical practitioners on tuber- culosis in pregnancy simply reﬂects the Public Health signif- icance of the condition. It is best described as a doubled- edged sword, one blade being the eﬀect of tuberculosis on pregnancy and the pattern of growth of the newborn, while the other is the eﬀect of pregnancy on the progression of tuberculosis. Tuberculosis not only accounts for a signiﬁcant propor- tion of the global burden of disease, it is also a signiﬁcant contributor to maternal mortality, with the disease being among the three leading causes of death among women aged 15–45 years [2]. The exact incidence of tuberculosis in pregnancy is not readily available in many countries due to a lot of confound- ing factors. It is, however, expected that the incidence of tu- berculosis among pregnant women would be as high as in the general population, with possibly higher incidence in developing countries. Earlier study by Schaefer reported a new case rate of 18–29/100,000 in pregnancy, which was similar to the 19– 39/100,000 reported for the city of New York [7]. A recent United Kingdom study, however, quoted an incidence of 4.2 per 100,000 maternities [8], which may be a reﬂection the current global fall in the incidence of the disease [2]. 5. Effects of Pregnancy on Tuberculosis Researchers from the days of Hippocrates have expressed their worries about the untoward eﬀects that pregnancy may have on preexisting tuberculosis. Pulmonary cavities result- ing from tuberculosis were believed to collapse as a result of the increased intra-abdominal pressure associated with pregnancy. This belief was widely held till the beginning of the fourteenth century! Indeed, a German physician rec- ommended that young women with TB should get married and become pregnant to slow the progression of the disease. This was practiced in many areas till the 19th century [9], while in the early 20th century, induced abortion was rec- ommended for these women [10, 11]. Researchers like Hedvall [12] and Schaefer [7], however, demonstrated no net beneﬁt or adverse eﬀect of pregnancy on the progression of TB. Frequent, consecutive pregnancies may, however, have a negative eﬀect, as they may promote recrudescence or reacti- vation of latent tuberculosis. Journal of Pregnancy It is, however, important to note that the diagnosis of tu- berculosis in pregnancy may be more challenging, as the symptoms may initially be ascribed to the pregnancy. The weight loss associated with the disease may also be temporar- ily masked by the normal weight gain in pregnancy. 6. Effects of Tuberculosis on Pregnancy The eﬀects of TB on pregnancy may be inﬂuenced by many factors, including the severity of the disease, how advanced the pregnancy has gone at the time of diagnosis, the presence of extrapulmonary spread, and HIV coinfection and the treatment instituted. The worst prognosis is recorded in women in whom a di- agnosis of advanced disease is made in the puerperium as well as those with HIV coinfection. Failure to comply with treatment also worsens the prognosis [13]. Other obstetric complications that have been reported in these women include a higher rate of spontaneous abortion, small for date uterus, and suboptimal weight gain in preg- nancy [14, 15]. Others include preterm labour, low birth weight and increased neonatal mortality [13]. Late diagnosis is an independent factor, which may increase obstetric mor- bidity about fourfolds, while the risk of preterm labour may be increased ninefolds [15–18]. 7. Tuberculosis and the Newborn Congenital tuberculosis is a rare complication of in utero tu- berculosis infection [19] while the risk of postnatal trans- mission is signiﬁcantly higher [20]. Congenital tuberculosis may be as a result of haematogenous spread through the um- bilical vein to the foetal liver or by ingestion and aspiration of infected amniotic ﬂuid [21]. A primary focus subsequently develops in the liver, with involvement of the peri-portal lymph nodes. The tubercle bacilli infect the lungs secondar- ily, unlike in adults where over 80% of the primary infections occur in the lungs [5]. Congenital tuberculosis may be diﬃcult to distinguish from other neonatal or congenital infections from which similar symptoms may arise in the second to the third week of life. These symptoms include hepato-splenomegaly, res- piratory distress, fever, and lymphadenopathy. Radiographic abnormalities may also be present but these generally appear later [13]. The diagnosis of neonatal tuberculosis may, how- ever, be facilitated by employing a set of diagnostic criteria developed by Cantwell et al. [22], including the demonstra- tion of primary hepatic complex/caseating granuloma on percutaneous liver biopsy at birth, tuberculous infection of the placenta, or maternal genital tract tuberculosis, and the demonstration of lesions during the ﬁrst week of life. The possibility of postnatal transmission must be excluded by a thorough investigation of all contacts, including hospital staﬀs and attendants. As much as half of the neonates delivered with congenital tuberculosis may eventually die, especially in the absence of treatment [7, 23–26].