Sperm Donor, Life Partner

Dawn Pieke’s relationship imploded just before she reached 40. Pieke had a miscarriage and shortly after, her boyfriend, whom she’d dated for almost a decade, met someone else on a business trip and had an affair. The two broke up and Pieke found herself in a tailspin: She knew she wanted a family, but she also knew her biological clock was ticking, and she wasn’t sure, after two separate, decades-long relationships, that she could go through it all again.

A glass of wine in hand, she steeled herself for more dating, signed up for Match.com, and started going on dates in Omaha, Nebraska, where she lives.

“I thought, ‘These guys look like jerks...I just want a kid, why can’t I just have a baby and not worry about if it’s the guy?’” she told me, in a phone interview. After eight months, she hadn’t clicked with anyone.

Pieke, who works in sales, started diligently researching her options, but soon got discouraged. Adoption didn’t seem like a good bet: She knew three separate couples trying to adopt, and it...