1990: Helping the embryo hatch
The Modern Laboratory · The Modern Papers
The Modern Papers · MP·07 · 1990
1990: Helping the embryo hatch
In Atlanta, a small opening in the shell helped embryos break free and implant.
The story
Before it can implant, an embryo must hatch from the zona pellucida, the clear shell around it. Jacques Cohen and his colleagues at Reproductive Biology Associates in Atlanta had already learned to open the zona with fine glass needles to help sperm in, a method they called partial zona dissection. Now they asked whether some embryos made in the laboratory struggled to get out.
Their 1990 paper reported that a small opening made by micromanipulation, which they called assisted hatching, improved implantation. The technique, and the argument over which patients it helps, has run through IVF laboratories ever since.
The museum's own time-lapse film of an embryo's first days, in Film and Photo, was recorded in the same Atlanta laboratory.
The paper
Impairment of the Hatching Process following IVF in the Human and Improvement of Implantation by Assisting Hatching Using Micromanipulation
J. Cohen, C. Elsner, H. Kort, H. Malter, J. Massey, M. P. Mayer, K. Wiemer
Human Reproduction 1990;5(1):7 to 13. January 1990. Read the paper.
Find it in the museum
How we know
Citation checked against PubMed (PMID 2324246) on 14 October 2026. No abstract is indexed; the account follows the sources on our Jacques Cohen page.
The IVF Museum · The Modern Papers
Compiled with AI-assisted research and checked against the original sources. Undergoing peer review. Corrections are warmly welcomed.
