NEW YORK—A wave of concern reportedly spread through the pharmaceutical industry this week as several major drug companies reported a dip in quarterly earnings, with experts placing the blame largely on the growing trend of mothers choosing to make vaccines for their children at home.

According to medical industry observers, the homemade inoculations, which are often assembled from scratch in kitchens or atop home craft tables, have become increasingly popular due to their low cost, their do-it-yourself appeal, and rising parental unease over the quality and origins of the ingredients in mass-produced immunizations.

“With some simple mail-order biochemical compounds and a little bit of elbow grease, mothers can now make and administer their own vaccines in the comfort of their own homes, saving themselves the expense and hassle of visiting a pediatrician,” said Deloitte senior business analyst Deborah Eisenson, who noted that the trend is spreading rapidly as more mothers post recipes and images of their handcrafted vaccines to Facebook and Pinterest. “In certain parts of the country, it has already become commonplace to see a continuous-flow centrifuge right there next to the microwave and the coffeemaker on the countertop.”

She added, “More and more of today’s moms want to know exactly what’s going into their children’s bodies, so they’re learning how to generate antigens from a home-grown chicken embryo or bacterial culture and then inject the vaccine into their child’s arm or upper thigh tissue themselves.”

Sources confirmed that groups of mothers across the country confer daily in online forums to swap their favorite vaccine-production methods for pertussis, diphtheria, polio, and other viruses, often suggesting adding little touches to the suspending fluid—such as customized blends of chemical compounds and antibiotics—to make the vaccine their own. In blog posts, moms reportedly share tips on ingredient-sourcing, dosages, and how to keep inactive viruses from going bad in the fridge, as well as how to make vaccinations fun by getting their kids involved in the process of making them.

When interviewed, many mothers described quality time spent gathered around the kitchen table, with the whole family helping to grind recombinant proteins with mortars and pestles while a supervising adult helps purify the mixture through chromatography and ultrafiltration. Others reportedly do prep work ahead of time on Sundays so that during the week they can simply come home from work, stir in any necessary adjuvants or stabilizers, and have an inoculation ready to go.

In addition, YouTube has become a popular resource for mothers, who log on by the thousands to watch step-by-step instructional videos on everything from isolating the latest influenza strains to making their oral typhoid solutions more palatable by stirring in a little apple juice.

One popular video, titled “Debbie’s Own Quick & Easy Mueller-Miller casamino acid medium,” currently has more than 23 million views.

“I know my vaccines are better for my kid because I make them with love and care in my own kitchen,” said Colorado Springs, CO mother Jen LaRochelle, adding that “God only knows what” drug companies are putting into their products. “When that immunizing serum flows through my daughter Samantha’s veins, I want to know she’s getting everything she needs. Making it yourself may take a little longer, but you get the hang of it pretty quick. A little aluminum hydroxide, a little ammonium sulfate, some polysorbate 80, and boom, it’s done in no time.”

“So far I’ve made my own tetanus and meningitis shots, and I’m working on an HPV one right now,” she continued, boasting that her all-natural injectables produce just as strong an immunity as the kind you get at the doctor’s office. “I get to grow the cultures myself using my favorite artisanal yeasts. It’s great.”

According to sources, homespun vaccinations are only one part of a larger do-it-yourself parenting movement in which moms and dads are producing handmade pills to treat hyperactivity, assembling their own orthodontics such as braces and retainers, and cooking up batches of insulin at home for children with diabetes. Experts predict that in years to come, the trend will only grow in popularity.

“Enough people were complimenting my measles vaccine that I now make a couple extra vials on purpose,” said Theresa Berman, a Fresno, CA mother of two, who revealed that her “secret ingredient” is a pinch of ginger. “It may not be as flashy as MMRV ProQuad, but it has the exact same WI-38 human diploid lung fibroblasts and MRC-5 cells as the brand-name variety.”

“Plus I print out my own cute little labels for the syringes,” she added. “Moms love it.”