The 28-day human menstrual cycle has been mimicked using “organ-on-a-chip” technology.

Researchers have demonstrated for the first time that various reproductive tract tissues can be successfully cultured together with other tissues for a full month.

Not only that, but they were observed releasing hormones found in a normal menstrual cycle.

The female reproductive tract consists of various tissues – the ovary, fallopian tubes, uterus and cervix – and these tissues have a range of functions, including the regulation of sex hormones.

Given the complexity of this interplay between tissues and hormonal control, it has been difficult to mimic such a process in the laboratory.

Teresa Woodruff and colleagues generated a microfluidic platform that can maintain five tissues together for a longer period of time than previously achieved.

In this device, fluid can flow over the tissues and they are under pressure, mimicking what happens in the body.

The authors combine mouse ovary with human fallopian tube, endometrium (the membrane that lines the uterus), cervix and liver tissue in the device for 28 days.

Peaks of oestrogen at the end of the follicular peak and the suppression of progesterone were observed, as seen in the menstrual cycle.

The current limitation of this work is that it only mimics hormone secretion and does not reflect the full function of the reproductive tract (to support offspring) or indeed show how other factors, such as the immune system, may affect this.

However, it is an important step in understanding reproductive tissue function, which could pave the way for future developments in drug discovery (contraceptive or fertility treatments) or toxicology studies.

The study is accessible here.