Wednesday, September 30, 2009

Embryo Swapping

Another example of 'patient mis-identification' with the patient in this case being either the wrong mother or the wrong embryo -- take your pick:

Note that in this case, the mother chose to continue the pregnancy even though the wrong embryo had been implanted. The article goes on to list a similar case where the mother chose to terminate the pregnancy.

Baby Swapping as Patient Mis-Identification

A 2003 story out of Boston highlighted a baby swapping incident as an instance of the broader problem of patient mis-identification:
In this particular case, the mother recognized that the infant given to her to nurse was not her own. What is of interest here is the frequency with which patient mis-identification occurs in hospitals -- with baby-swapping being only a particular example. Despite elaborate procedures to prevent these cases, they occur with depressing regularity.

Friday, June 12, 2009

Preferential Childcare Based on Appearance

New Scientist has an interesting article up this week on variations in the amount of time and resources fathers devote to their children. The study, done in Senegal, found that fathers devoted greater time and resources to children who looked and behaved more like them regardless of gender. Here’s the link:

The authors speculate that in the absence of proof of paternity, fathers look for similarities to themselves when they apportion scarce resources. They link this preferential treatment to the uncertainties of fatherhood.

It would be interesting to follow up this study with one that simultaneously looked at the frequency of non-paternity events in a culture. One would predict that in cultures where the rate of NPEs was high (as determined by DNA testing) the imbalance in preferential treatment based on appearance would be greater.

Monday, May 18, 2009

Twin Half Brothers

In the news this week from Texas, a case of ‘twin’ boys fathered by different men. Their mother was having sex with both men and one ovum was fertilized by sperm from each man. DNA tests were ordered when the twins looked substantially different from each other. Here’s the link:,23599,25500537-2,00.html


Wednesday, May 13, 2009

More Baby Swapping

Another instance of baby swapping surfaced in the press this week. Although the actually swapping occurred in 1953, the exchange of two baby girls in a hospital in Washington state only came to light recently. DNA testing confirmed that the girls had been exchanged while being bathed by nurses. Here’s a link:



Monday, April 20, 2009

Adoption via Kidnapping

An article in the New York Times provides a story about child abduction in China that illustrates by contrast some of the cultural biases in Western/European culture regarding non-paternity events. Some time ago China implemented a one-child policy in order to stem population growth. In a society that traditionally relied on sons to support parents in the old age, this meant that some families with a girl were left without sons. In response, an illegal market has developed for kidnapped toddler boys – stolen from their parents, these boys are sold to families who want a son. This forced adoption results in what is clearly an NPE, but certainly of a different sort than we usually consider.

The article is at:

Friday, April 10, 2009

Cryopreservation World Record

We’ve previously mentioned the potential problem of asynchrony brought about by cryopreservation technology. That is, a man could have his sperm frozen and it could then be used at a much later date to fertilize an ovum. Today’s news brings this example:

“CHARLOTTE, N.C., April 9 /PRNewswire/ -- Fertility specialists of Reproductive Endocrinology Associates of Charlotte (REACH) herald the successful birth of a baby girl March 4 who was conceived through in vitro fertilization (IVF) at their laboratory with sperm frozen for 21 years, which they believe ties the world record for the longest-frozen sperm used to create a baby with IVF.”

The complete article is found at: