Don’t worry, ladies: Once you’re pregnant, having sex won’t get you pregnant again — even though an Arkansas woman carrying two babies of two gestational ages claims it happened to her.
“You can have sex usually with wild abandon and not worry about getting pregnant a second time. Normal sex throughout a pregnancy is not an issue,” NBC chief medical correspondent Dr. Nancy Snyderman told TODAY’s Matt Lauer Monday in New York. “The chances of getting pregnant [again], even early on, are infinitesimally small.”
Snyderman’s medical opinion is shared by other doctors and obstetricians, who are skeptical that Julia Grovenburg of Fort Smith, Ark., is carrying two babies conceived 2½ weeks apart — which would be an example of an extremely rare phenomenon called superfetation. Far more probable, they say, is that she is carrying twins who are growing at different rates.
“The most likely explanation is that this is a normal twin pregnancy with a significant discrepancy in the sizes of the two fetuses because they’re developing at different rates,” Dr. Ralph Kazer, chief of reproductive endocrinology at Northwestern Memorial Hospital, told NBC News.
The doctors can say what they want, Julia and Todd Grovenburg, the expectant parents, told Lauer from their Fort Smith home. The two fetuses — Jillian and Hudson — have consistently been shown by ultrasound tests to be two weeks and four days apart in their development.
“Beyond a shadow of a doubt, we believe it’s superfetation and that there is no slower development for the smaller child,” Julia said.
The Grovenburgs had been trying to start a family for three years when a home pregnancy test six months ago revealed that Julia was finally pregnant. But when the couple went in for their first ultrasound look at the fetus on June 4, even the technician doing the test was astonished.
“I gagged,” Julia told Lauer with a laugh when asked to describe her initial reaction. “It was very shocking for there to be two, but for there to be two that appeared to be of two different ages — it was surreal.”
Todd’s reaction was different. “He laughed a lot,” Julia said, as her husband nodded in agreement.
Some have suggested that the Grovenburgs are pushing the superfetation story because of the international publicity the story has generated. Julia dismissed that charge, saying if that were true, they would have gone public months ago.
“For us, it’s ridiculous,” she said of the charges. “We waited over five months to let this story air, even with our local media, until we got confirmation that the suspicion was real, and that it was a possibility and not just something in our head. Now that they said it is a possibility, that’s when we decided to tell our story.”
Fooling Mother Nature?
The reason for the skepticism lies in biology. Snyderman said that when a woman becomes pregnant, powerful hormonal changes prevent the fertilization and implantation of a second embryo, even in the rare instances when a woman ovulates twice during one monthly cycle.
The medical literature on superfetation is more anecdotal than scientific. Some researchers say there are approximately 10 confirmed cases of the phenomenon. And the Grovenburgs’ obstetrician, Dr. Michel Muylaert, believes that Julia Grovenburg may join them.
“Mrs. Julia Grovenburg is pregnant with twins and there appears to be a discordant growth pattern, possibly due to superfetation. This is an unusual and rare condition, but the possibility is real,” Muylaert said in a statement released to the media. “It can only be confirmed after delivery by chromosomal and metabolic studies on the babies. She was evaluated at UAMS in Little Rock for this condition and they confirmed the suspicion of superfetation.”
An amniocentesis could confirm superfetation, but the Grovenburgs have decided against that test because of possible danger to the fetuses. Instead, they said they will allow the babies to be tested after birth to determine if they are fraternal twins growing at different rates or the result of two fertilizations more than two weeks apart.
“If the test is available to be done after they arrive, that is something that we definitely will do,” Julia told Lauer.
Julia is both 25 and 28 weeks along in her unusual pregnancy, which means that Jillian’s due date is in late December and Hudson’s in early January. The Grovenburgs’ doctors have planned a Caesarean delivery of both babies in December, which is just fine with the couple.
“I think it’s going to be good on the taxes,” Todd observed.