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Interview study designed to investigate association between mode of first delivery and subsequent fertility

Kristen Kjerulff photo

Kristen Kjerulff, Ph.D.

Ongoing research at the Penn State Hershey Medical Center explores the effect of caesarian section on subsequent fertility. In previous studies conducted in countries throughout the world it was discovered that mothers who deliver by caesarian section are less likely to have subsequent children for reasons that are not clear. “This is a mystery that we need to understand,” said principal investigator Kristen H. Kjerulff, Ph.D. Most researchers in this subject area survey women retrospectively—after the birth has taken place—or review very large data sets that do not indicate the reasons why the caesarian section option was chosen and why the women did not have more children. Kjerulff’s First Baby Study is novel in that it interviews pregnant women before they have their first baby and then at multiple points over the course of a three-year period, to see how mode of first delivery (cesarean, instrumental, or vaginal) affects subsequent childbearing and, if so, why.

This study has enrolled more than 3,000 women from all parts of the Commonwealth of Pennsylvania. Kjerulff and her colleagues sought a diverse population across socioeconomic strata, racial and ethnic groups, and insured/uninsured populations. They recruited participants from hospital ob-gyn clinics; Nurse-Family Partnership programs; child birth education classes; low-income patient clinics; private ob-gyn practices; hospital tour groups; Women, Infants, and Children (WIC) program offices; and Medicaid programs. Researchers from the various hospitals around the state helped enroll and consent women interested in participating in the study, reviewed data, and provided advice on various aspects of the study.

The First Baby Study team of investigators includes John T. Repke, MD, FACOG , and John J. Botti, MD, ACOG from Obstetrics and Gynecology; Ian M. Paul, MD, ’98, from Pediatrics; Cynthia H. Chuang, MD, M.Sc., Jennifer S. McCall-Hosenfeld, M.D. and Jennifer L. Kraschnewski, MD, M.P.H. from Internal Medicine; Kesha Avalon Baptiste-Roberts, PhD, and Cara Bicking, M.S., R.N.C., from Nursing; Mary E. McAlevy, M.D. from Anesthesiology; Marianne Hillemeier, PhD, from Health Policy and Administration, and Carol Weisman, PhD, and Junjia Zhu, Ph.,D., and Diana Velott from Public Health Sciences. Each member of the investigator team is studying different aspects of the childbearing process to improve understanding of what women and their families are experiencing as they have their first babies and consider adding to their families over the course of time.

Further, the team is investigating the many possible predictors of whether a woman has a second baby, including the first baby’s health, mother’s health, relationship between the mother and her partner (if applicable), mother’s exercise and eating habits, and financial considerations. Over a three-year period, researchers will conduct 24,000 interviews and follow-ups with participants (eight interviews per participant) to see whether they have a second baby within that time period. The results of this study will inform clinical practice and may well help to shape public health policy in the future. “Drop-out rates are low for our study,” reported Kjerulff.

“Women are interested in the study and very helpful. We are investigating issues that they care about. All considered, this has been a very good process so far. By the end of our study, we will have collected lots of important data.” She added, “Because we’re breaking new ground with our study, the data that we’ve collected so far has been surprising.
– By Alicia E. Riegel-Kanth, M.P.A.

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