# Presentation: 699297

## Trends in Mode of Delivery and Neonatal Complications in New Jersey, 1997-2005

- Neetu J. Jain BHMS MPH
- Lakota K. Kruse MD MPH
- Kitaw Demissie MD PhD
- Meena Khandelwal MD
- New Jersey Department of Health and Senior Services
- Maternal and Child Health Epidemiology
- MICHEP Conference - December 12th 2007
- _[Neetu.Jain@doh.state.nj.us](mailto:Neetu.Jain@doh.state.nj.us)_

**Notes:**
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## Background

- Nationally as well as in New Jersey overall deliveries by cesarean section are on the rise, while instrumental and unassisted vaginal deliveries are declining.
- In 2006, New Jersey cesarean delivery rate were 37%, higher than national average rate.
- This change in trends may have also had an impact on the short and long term maternal and neonatal outcomes.

**Notes:**
Over past couple of years NJ has been ranking among the first top 5 states. In 2006 NJ had 37% cesarean section.  The rates are increasing steadily over the time.  With this increasing trends there has been concern regarding the direction of the trends for short and long term maternal and neonatal complications. 

## Study Question?

- What are the trends in the risk of selected neonatal complications associated with mode of delivery?
- Do the changing trends in mode of delivery have an impact on neonatal complication rates?
- Compare relative risk of  specific neonatal complications by cesarean trial of labor and cesarean no trial of labor vs. Vaginal delivery
- Are there any covariates that are confounding these trends?
*Gestational Age*
*Mother’s medical risk factor*

**Notes:**
Do risks of neonatal complications vary by MOD?
Have changing trends in MOD impacted neonatal complication rates?  

Results
MOD is changing.  Increasing CNTL and CTL.
CNTL and CTL have higher rates of RDS, IVH, and TTN, but not Injury.
Complication rates need to be examined by specific complication and MOD
Complication rates for RDS, IVH and TTN by MOD have decreased or remained level 
TTN has increased for CNTL)
Gestational age is an important factor in examining specific complication rates and trends

## Method and Subject Selection

- Created a linked perinatal dataset by matching New Jersey’s 1997 to 2005 electronic birth certificate (EBC) records to hospital discharge (UB) records for mothers and newborns, resulting in a total of 1,004,116 records (births).
- This linked perinatal dataset including EBC and UB data will provide us an opportunity to examine trends in outcomes and comparisons by method of delivery for all New Jersey births.

## Data Source

- The International Classification of Disease (ICD-9-CM) codes from UB records and check boxes from EBC records were used to identify the mode of delivery and selected neonatal complications.
_**Mode of Delivery:**_ Categorized into;  Instrumental Delivery, Unassisted Vaginal Delivery, Cesarean/Trial of Labor and Cesarean/No Trial of Labor.
_**Neonatal Complications**_: Respiratory Distress Syndrome, Transient Tachypnea of Newborn, Intraventricular Hemorrhage and Injuries to the Newborn.

## Diagnostic Codes

- ICD-9 codes Neonatal Complication:
- Respiratory Distress Syndrome: 769
- Transient Tachypnea of Newborn: 770.6
- Intra-Ventricular Hemorrhage: 772.1
- Injuries: 767.1 (brachial), 767.2 (clavicle), 767.3 (skeleton) and 767.6 (scalp).
*Check boxes from EBC were used for Respiratory Distress Syndrome and Transient Tachypnea of Newborn*
*	**	**	**	**	**	**	*

**Notes:**
Primarily ICD-9 codes were used for categorizing these complications.  If EBC was available then the combination of both were used thus trying to capture all the information.

## Trends in Mode of Delivery in NJ, 1997-2005

**Notes:**
In this slide we looked at trends by mode of delivery for all mothers who delivered between 1997-2005. There was steady rise in both cesareans and decline in vaginal delivery.  
Cesarean delivery/no trial of labor that increased from 11.6% to 21.5% for 1997-through 2005.
Cesarean/trial of labor also increased from 12.8%-14.0% for the same time period. 
Instrumental delivery decreased steadily from 9.8% - 5.5% and so did 
Unassisted vaginal delivery decreased from 65.3% - 57.6%.

## Trends in Select Neonatal Complications in NJ, 1997-2005

**Notes:**
In this slide we looked at trends in selected neonatal complications for all the babies delivered between 1997-2005.
-TTN increases over the time period from 3.3 – 3.9
-So does RDS increases from 2.1-2.4
-There is a sharp decline in Injuries from 4.1 – 2.6
-IVH remains the same for all the years		

## Respiratory Distress Syndrome by Mode of Delivery

**Notes:**
RDS is a very common complication (1-6/100).

RDS slightly increase for Instrumental delivery, while gradually declines rest of mode of delivery.

Very Large differences by MOD.  Highest for CS No Trail Labor, then CS with Labor

## Intra-Ventricular Hemorrhage by Mode of Delivery

**Notes:**
IVH is a less common complication (.08-.8/100).

IVH declined drastically for cesarean/no trial of labor. For rest of them it slightly declined or remain stable over time. 

Very Large differences by MOD. Highest for CS No Trail Labor, then CS with Labor

## Transient Tachypnea of Newborn by Mode of Delivery

**Notes:**
TTN is a common complication (2-6/100).  Somewhat related to RDS
It is increasing over time for C/NTOL. C/TOL, Instrumental but steady for vaginal.
Except Transient Tachypnea all the complications are either declining steadily or are stable over time period across all method of delivery.

Large differences by MOD. Highest again for CS No Trail Labor, then CS with Labor

Introduce concept of covariates (mention possibility of changes in gestational age... effecting trend)

## Injuries in Newborn by Mode of Delivery

**Notes:**
Injuries are a common complication (4-12/100).

Different pattern then 3 prior slides.  Very Large differences by MOD. Highest for Instrumental (as expected)

Injuries declined but bumped up again in 2005. It slightly showed increase for cesarean delivery/no trial of labor too.
Transition to next 2 slides comparing relative risk of specific complications, to see if any specific time periods contribute more to increase/decrease in these trends.

## Relative Risk: Cesarean After Trial of Labor v. Vaginal Delivery

**Notes:**
First focus on magnitude of higher risks (1.5 – 2) for RDS, TTN & IVH for CATL verse Vaginal
Only low risk for injuries (as expected).

Injuries, IVH & RDS increased for 2003-2005 as compare to 2000-2002.  For 2003-2005 time period , Injuries had 1.10times higher 
Risk for catl vs. vaginal.  All other NC were higher than 2 for CATL compare to vaginal.

## Relative Risks: Cesarean/No Trial of Labor V. Vaginal Delivery

**Notes:**
First focus on even higher magnitudes of risks (2.5 – 5) for RSD, TTN & IVH for CNTL verse Vaginal
Only low risk for injuries (as expected)

For time periods, Injuries did increase but still had very lower risk than VD. Similarly TTN also increased and had 2.9 times higher risk than vaginal.  IVH & RDS did decrease for the latest time period although it had very high risk than vaginal.

## Explanation for these declining trends?

- Cesarean and complication are not rising in parallel:
- Are there some underlying factors/covariates that are confounding the risk of the mode of delivery on these complications.
- So the first step we took was to explore the relation of the gestational age to individual complication and compare by mode of delivery irrespective of the time period.

**Notes:**
Although cesarean/TOL & C/NTOL have higher risk than vaginal delivery, they are decreasing over time inspite of increase in cesarean rate.
So we went one step further and after the input from our collaborators we decided to look at the following covariates.
The next set of slides we looked at the very most important covariate that could help us to explain these decline in trends for neonatal complication.

## Respiratory Distress Syndrome by Mode of Delivery & Gestational Age

**Notes:**
RDS: Higher rates were seen in Cesarean/Trial of Labor and Cesarean/No Trial of Labor as compared to unassisted vaginal delivery. 
For all the mode of delivery the higher rates were seen in earlier gestational weeks and declined rapidly near term and at term.

## Intra-Ventricular Hemorrhage by Mode of Delivery & Gestational Age

**Notes:**
IVH: On the contrast IVH had higher rates in Unassisted Vaginal Delivery as compare to Cesarean/Trial of Labor and Cesarean/No Trial of Labor. IVH was also seen to be more prevalent in earlier gestational age and declined rapidly. Labor is a risk factor for IVH

## Transient Tachypnea of Newborn by Mode of Delivery & Gestational Age

**Notes:**
TTN: The higher rate of TTN was seen in Cesarean/No Trial of Labor for near term (late pre-term)(33-36 weeks) and term newborns.

## Injuries in Newborn by Mode of Delivery & Gestational Age

**Notes:**
Injuries: Instrumental Delivery had the highest rate followed by Unassisted Vaginal Delivery, Cesarean/Trial of Labor and least in Cesarean/No trial of Labor.

## Results for Gestational Age Stratification

- Stratification based on gestational age shows that gestational age is very important for all of these neonatal complications.
- IVH have higher incidence in early preterm newborns (24-30 weeks), while RDS has higher incidence in late preterm newborns (32-34), while TTN & Injuries is more prevalent in near term newborns (34-37weeks).

**Notes:**
Thus just looking at the trend in these complications by mode of delivery; it seems like that gestational age is an important for all of the selected NC. RDS & IVH have higher incidence in preterm newborns (32-34 weeks), while TTN & Injuries is more prevalent in near term newborns (34-37weeks). As we expected we found these results.

## Trends in Mother’s Medical Risk Factors

**Notes:**
All the medical risk factors were taken from EBC (27 MRFP); They were 
Severe : Cardiac, coma, diabetes-insulin, diabetes-non-insulin, gestational diabetes, eclampsia, hemoglobinopathy, hydraminos/oligominos, hypertension-chronic, pregnancy-induced hypertension, Incompetent cervix, lung disease, pre-eclampsia, previous macrosomia, previous major uterine surgery, previous SGA, renal diseases, seizure, Uterine bleeding---- 14.11%
Mild: Anemia, Herpes, Hepatitis B Other Medical risk factor, RH sensitization, other isoimmunization, STD, syphilis. :  (24.4%)

Gradual drop in none with increase in mild (10.1-12.7).  Severe increased from (10.10-11.5)
Results/graphs not shown demonstrated that MMRFs were not:  We also analyzed the trend by MRFP for all the selected neonatal complications and the results did not shown any significant trend.

## Limitations

- Reliance on coding of ICD-9 neonatal complications.
*Limited to 9 discharge diagnoses.*
*Coding changes over time.*
- Under-reporting of mothers medical risk factor during pregnancy in both these datasets.

## Conclusion

- Overall trend for neonatal complications are either decreasing or leveling off.
- Relative risks hasn’t change much over 3 time periods.
- Gestational age is important for all the complications we looked at.

**Notes:**
Overall trend for neonatal complications are either decreasing or leveling off. 
	reassuring but unexplained and could complications be reduced further
Relative risks hasn’t change much over 3 time periods.
	if risks are improving for all MOD, what changes are driving improvement? High-risk pregnancy management?
Gestational age is important for all the complications we looked at.
	how does gestational age effect neonatal complications by MOD?
	are interventions leading to deliveries that are too early?
	are gestational ages and lung maturity being accurately assessed before interventions (late-pretern vs term)?

## Further Research Agenda

*The next steps would be to control for:*
- Analyze the interventions
*Prenatal steroids for the mothers.*
*Surfactant therapy for the newborn.*
- Re- analyze the trend for these complications by mode of delivery after adjusting for gestational age to see if cesarean and complications are rising in parallel?

**Notes:**
Next steps
Adjust for gestational age

Examine dataset for possible explanatory interventions (i.e. steroids, surfactant)

## Collaborators

- We are jointly working with clinicians (Obstetricians & Neonatologists) and researchers who are expert and knowledgeable in this field:
- Dr. Kitaw Demissie, MD, PHD; Division of Epidemiology: Associate Professor at UMDNJ-SPH.
- Dr. Meena Khandelwal MD; Division of Maternal Fetal Medicine: Associate Professor at Cooper Hospital.
**THANK YOU****	****	****	****	****	**