Synopsis: Kate and Ken Stevens decide for him to get a vasectomy after her fourth pregnancy, as she cannot use birth control. While doing so frees them from worries about pregnancy, their sex life crashes after she delivers the baby due to postpartum depression and other issues.

One night, Kate catches Ken watching porn, which starts a fight. She realizes that his sexual needs are unmet, and that he has never complained about this. They end up exploring porn together, which leads to rekindled interests in threesomes.

The couple partakes in some threesome fun, but they aren't as careful as they perhaps should have been...

Note: this is a long story - about 38k words.

Preview:

Kathryn Stevens sat nervously perched on the edge of her toilet seat, studiously avoiding looking at the plastic stick in her hand. She was nine days late at this point, and her body felt off in a familiar way… so she had decided that it was time to be sure.

It was really only a matter of time, she supposed. She and her husband Ken never used condoms – she had made a painful, itchy discovery as a teen that she had a latex allergy. Kathryn – Kate (but never Katie) to her friends - had used various other methods of birth control over the years, but none of them were great for her. The pill made her gain weight, made her moody, and tanked her libido. The ring was better, but she didn’t like the weird bleeding she was prone to while on it. The damned shot, while convenient, caused an allergic reaction that got worse every single time she got it - to the point that Ken had forbidden it as an option after her hives had included trouble breathing the last time the doc had given it to her. Kate had unsuccessfully tried an IUD years ago, but the bleeding just never seemed to stop; she wasn’t keen on giving that another go. She had used the pill for years as the best of a bunch of bad options, but she had reached her wits end with it.

Six months ago, Kate had decided to not refill the pill, and holy shit had she been so much happier off of the damned thing. The fifteen pounds she had struggled with for the past couple of years seemed to just melt away. She was happier, more confident, vibrant. Ken had appreciated the changes in her attitude (to say nothing of the massive jump in her sex drive) so much that it didn’t take much convincing for him to agree to say to hell with the pill. They had chosen to go back to pulling out… but the fact was that they had NEVER been very good at it – their first three children were evidence of that.

Well, evidence of that and of Kathyrn’s high fertility. She had two friends who had struggled with getting pregnant, and she knew that it was normal for most people to have to try for months… but Kate herself had the opposite issue. It seemed that Ken had to only look at her the wrong way, and that poor rabbit was as good as dead.

She’d been off of contraception for six months now, and they had quickly moved from pulling out every single time to pulling out only on risky days. Kate’s cycle had always been clockwork regular – bleed for two to three days, ovulate on day fourteen. Every time.

She and Ken had joked about it – once, they had gone so far as to chart her periods ahead of time on a brand new calendar for the entire coming year. She was only off by a single day on one period for the entirety of those twelve months.

In theory, they should have been pretty safe. In practice, the couple were their own worst enemies when it came to safety. Both Ken and Kate absolutely loved it when he came inside of her. Kate always felt a little unfulfilled, a little hollow if he pulled out. And Ken loved to fill his wife up; he always said that it just felt like his cum belonged inside of her. As a result, neither of them were super wonderful at insisting on proper pulling out; he would often push the absolute limits of his ability to hold back his orgasm, she would often lock her legs around him and try to get him to stay inside for a few extra seconds when he was ready to come.

Given these tendencies, given how they kept pushing things right up to the risky days, it really was only a matter of time. And so, here she was, thirty-eight years old and a mother of three, feeling like the three minutes for the pregnancy test to give an answer was more like three hours. Finally though, the time was up, and Kate turned the test over.

There it was – the faint but unmistakable second blue line that she had known she would see. Baby number four was on the way.

Now, Kate just had to figure out how to tell her husband.

Complete story post on Literotica: A Taste of Kate