Fetal Lung Maturation in Twin Gestations

Objectives:

To evaluate discordance in lung maturity in diamniotic twins based on birth order, sex and body weight. If we find discordance in fetal lung maturity in twin gestations this will change current practice of sampling only one amniotic sac for evaluation of fetal lung maturity.

Hypotheses:

Lung maturation within twin pairs is weakly correlated based on presentation and estimated fetal weight.

Research Methods:

This study will be prospective cohort study of women with twin diamniotic intrauterine gestations who will be delivered at a Good Samaritan or Bethesda North Hospital. Patients will be counseled and informed consent for participation in the study will be obtained prior to enrollment in study.

At the time of Cesarean delivery or in the event of amniocenteses for FLM, a sample of amniotic fluid will be drawn from the amniotic sac of Twin A and Twin B. Each amniotic sac will be aspirated by the obstetrician and sent to the laboratory for determination of fetal lung maturity index and lamellar body count. Fetal lung maturity index and lamellar body count will be correlated to see if there is an association between Twin A and Twin B.

Fetal Lung Maturity index and lamellar body count will be calculated and compared based on fetal weight, sex, zigosity, and birth order. Demographic information, maternal obstetrical and medical history, newborn/fetal data, indications for cesarean section and twin A and B outcomes will be obtained through OB Traceview or patient chart.

Study population:

Participants will include pregnant patients, greater than 24 completed weeks with diamniotic twin gestations, at Good Samaritan and Bethesda North Hospitals. Patients will be scheduled for a cesarean section by their primary MD prior to being approached for inclusion into the study.

Inclusion criteria

Diamniotic twin gestations

• Twenty-four completed weeks gestation with dating calculated by their sure last menstrual period or utilizing a first trimester crown rump length ultrasound.
• English Speaking
• Scheduled cesarean section by patient's primary MD

Exclusion criteria

• Monoamniotic twins
• Presence of gross blood in amniotic sample
• Presence of meconium amniotic fluid
• Known/diagnosed fetal or newborn anomaly
• Twin to Twin Transfusion Syndrome (TTTS)
• Vaginal delivery