Heartburn and Baby Hair

“I’ve got a lot of heartburn – I guess that means my baby will have lots of hair.” This is one of the more common sayings in a doctors office. I used to think there was no truth to this one until an article came out in 2006 from doctors at Johns Hopkins University(1) which looked at mothers with reported heartburn and there subsequent offspring. In this study 64 women were enrolled (admittedly a small number) and they ranked their degree of heartburn. This was subsequently linked to an evaluation of the infants hair by independent coders using photos of the infants heads shortly after birth. Interestingly, their symptoms of heartburn severity was not related to fetal gender but it was related to hair growth.
When plotted out the relationship is nearly linear. 23 of 28 women who reported moderate or severe heartburn has infants with average or above average hair but 10 of 12 women who reported little or no heartburn had infants with less than average or no hair.

Fetal Heart Rate and Gender

Gender Prediction From Fetal Heart Rate

Perhaps the most common myth of pregnancy is the idea that gender of the fetus can be predicted from the fetal heart rate. This is not true and has been proven so with numerous studies.

One study in 1980(1) tested the hypothesis that the sex of the fetus could be determined by the fetal heart rate – it looked at 250 male and 250 female fetuses and was not able to support the hypothesis.

One Study done in 1986 which initially documented the differences of the baseline fetal heart rate at different weeks of gestation (2)This study sis show that there was a difference in the heart rate from 19-24 weeks gestational age and 36 to 40 weeks, it studied 37 patients and showed the baseline heart rate was not significantly different between male and female fetuses.

An additional study published in the Journal of Diagnostic Sonography in 1989 (3) confirmed this these findings.

Another study done in 1996 (4) looked at fetal heart rate as well as “Maternal Intuition” among 212 patients and found no difference in the baseline fetal heart rate between male and female fetuses at any gestational age. In addition the accuracy of “Maternal Intuition” was no better the random guessing.

As if this wasn’t enough, another study done in 2006 (5)which enrolled 477 patients – again no statistically significant differences between the heart rate of male and female fetuses was observed.

Since fetal heart rate itself did not correlate with gender at all, investigators decided to look at fetal heart rate variability. In 2005 (6) a study looked at the actual beat to beat variability to determine if there was any difference between genders and found none.

1. Petrie B, Segalowitz SJ. Use of fetal heart rate, other perinatal and maternal factors as predictors of sex. Percept Mot Skills 1980 Jun;50(3 Pt 1):871-874.[cited 2011 May 15 ]

2. Druzin ML, Hutson JM, Edersheim TG. Relationship of baseline fetal heart rate to gestational age and fetal sex. Am. J. Obstet. Gynecol 1986 May;154(5):1102-1103.[cited 2011 May 15 ]

3. DuBose TJ, Porter L, Dickey D, Hill LW, Butschek CM, Poole EK. Sonographic Correlation of Fetal Heart Rate and Gender. Journal of Diagnostic Medical Sonography 1989 Mar;5(2):49 -53.

4. Genuis S, Genuis SK, Chang WC. Antenatal fetal heart rate and “maternal intuition” as predictors of fetal sex. J Reprod Med 1996 Jun;41(6):447-449.[cited 2011 May 15 ]

5. McKenna DS, Ventolini G, Neiger R, Downing C. Gender-related differences in fetal heart rate during first trimester. Fetal. Diagn. Ther 2006;21(1):144-147.[cited 2011 May 15 ]

6. Ogueh O, Steer P. Gender does not affect fetal heart rate variation. BJOG: An International Journal of Obstetrics & Gynaecology 1998;105(12):1312-1314.