Karleen Oberton
Chief Financial Officer at Hologic
Thank you, Essex, and good afternoon, everyone. In my statements today, I will provide an overview of our revenue results, walk down our income statement showcasing strong performance, touch on certain key financial metrics, and finish with our guidance for the fourth quarter and full fiscal 2024.
Our third quarter financial results were robust, once again exceeding our expectations on revenue and profitability, building on the momentum from the first half of the year. To recap high level results, total revenue came in at $1.011 billion, beating the midpoint of our prior guidance by $11 million. We delivered 3.1% revenue growth and organic growth of 5.8%, excluding COVID. In addition, non-GAAP earnings per share were $1.06, growing 14% and exceeding the high end of our prior guidance by $1.00.
Before moving on to our franchise results, we want to highlight the continued strength of our balance sheet. In Q3, we generated over $400 million in cash from operating activities, ending the quarter with $2.4 billion on the balance sheet, deployed $100 million on share repurchases, and announced the acquisition of Endomagnetics.
We continue to demonstrate that our strong cash balance, leverage ratio well below our target range, and ability to generate cash consistently provide us the flexibility to fund innovation and pull both levers of our capital allocation strategy, tuck-in M&A and share repurchases, at the same time. Moving forward, we still have significant firepower to continue to deploy capital diligently, as opportunities arise.
Turning to our franchise results. In Diagnostics, third quarter revenue of $440.8 million, grew 0.7%. Excluding COVID assay and related revenue, worldwide Diagnostics grew by 6%. Within Diagnostics, Molecular Diagnostics continues to contribute significantly, growing 10.5% excluding COVID. We continue to see underlying strength in BV CV/TV, which continues its outstanding growth trajectory and has become our second largest assay globally.
Additionally, as expected, non-COVID respiratory assay sales declined sequentially from Q2, in line with the flu season. However, year-over-year growth remains strong, highlighting the continued adoption of our 4-plex COVID, Flu A, Flu B, and RSV assay. And finally, Biotheranostics continues to be accretive to growth for our Molecular business.
Rounding out Diagnostics, Cytology and Perinatal declined 2.9% globally, with US declines partially offset by solid international growth, as Essex highlighted earlier. As a reminder, in fiscal Q3 [Phonetic] '23, customers built up cytology inventory levels in the US, due to third-party shipping constraints in Q2 '23, leading to elevated sales in the prior year period. While the cytology business has largely returned to normal, year-over-year growth rates were impacted. Looking ahead, we expect flat to modest growth from the cytology business.
Moving on to Breast Health. Total third quarter revenue of $385 million increased by 7.1%, or 8.2%, when excluding SSI. Within Breast Health, growth was primarily driven by Breast Imaging, with solid domestic and international results, contributing 7.2% and 12.1% growth, respectively, excluding SSI. Third quarter performance was driven largely by increased gantry shipments and robust service revenue growth that continues to contribute meaningfully.
Continuing next to Surgical. Third quarter revenue of $166.6 million, increased 6.2%. Surgical growth continues to be fueled by MyoSure and the related Fluent Fluid Management System. Our Laparoscopy business, while smaller in dollars, grew significantly in the quarter and continues to progress nicely. Additionally, International continues to be a bright spot, growing just under 20% in the quarter.
Finally, in our Skeletal business, third quarter revenue of $19 million declined 29.7% due to lower Horizon DXA shipments resulting from a temporary stop-ship related to a non-conformance issue. We are working with our suppliers to resolve this situation and expect to resume shipments during the first quarter of fiscal 2025.
Now, let's move on to the rest of the non-GAAP P&L for the third quarter. Gross margin was 61.1% for the quarter, a 30 basis points improvement from the prior year period, even though COVID assay revenue declines continue to be a headwind. Additionally, gross margin expanded 40 basis points sequentially from fiscal Q2, primarily driven by favorable product mix.
Total operating expense of $302.8 million in the third quarter decreased by 3.5%. This decrease was driven primarily by elimination of expenses related to the divested SSI businesses. Operating margin was 31.2% for the third quarter. The year-over-year increase of 230 basis points was driven by top line growth, expanding gross margins, and lower operating expenses. Sequentially, as expected, operating margins expanded 20, I'm sorry, 80 basis points from Q2, largely from lower operating expenses and higher gross margin in Q3.
Below operating income, other income, net, represented an expense of nearly $3 million in our fiscal third quarter. Interest income is lower due to lower cash balances from the significant share repurchases we have completed throughout the fiscal year. Additionally, interest expense is up due to higher interest rates. Finally, our tax rate in Q3 was 19.75% as expected.
Now let's move on to our non-GAAP financial guidance for the fourth quarter and full year fiscal 2024. For Q4 2024, we are expecting total revenue in the range of $970 to $985 million and EPS of $0.97 to $1.04. For the full year, fiscal 2024, our guidance assumes revenue of $4.012 billion to $4.027 billion; and EPS of $4.04 to $4.11.
Unpacking this guidance, we lowered the midpoint of our prior revenue guidance by $5 million, which represents about a $20 million headwind related to the temporary Skeletal Health stop-ship previously mentioned, partially offset by our strong performance in Q3, and the inclusion of an estimated $4 million to $5 million of revenue from Endomagnetics now that we have closed the acquisition.
With respect to foreign exchange, we are assuming Q4 will have a headwind of about $3 million. For the full year, we now expect a slight tailwind of about $3 million. Turning to our franchises, we expect Diagnostics, Breast Health, and Surgical to grow mid-single digits in Q4 and full year fiscal 2024, excluding the impact of COVID. As a reminder, fiscal '24 has four fewer selling days compared to fiscal '23, which we estimate to be a headwind of more than 100 basis points for the full year.
Starting with Diagnostics. In Q4, we expect our Molecular Diagnostics business to drive high single-digit growth, excluding COVID, as customers continue to adopt and drive utilization of our broad Panther menu.
In Cytology and Perinatal, we expect growth in the mid-single digits for the fourth quarter. Sequentially, however, we expect the business to perform flat to Q3. In Q4 of last year, sales dropped below typical ordering patterns due to inventory build-up in Q3 of '23. We expect Cytology and Perinatal comps to stabilize in fiscal year '25.
Closing out on non-COVID Diagnostics, we expect Blood revenue of approximately $6 million in Q4 and $20 [Phonetic] million for the year. In terms of COVID revenue, we expect COVID assay sales to be about $7 million in Q4 '24, and about $70 million for the full year. COVID-related items are expected to be about $25 million in the fourth quarter and approximately $105 million for the full year.
Moving on to Breast Health. We remain on pace to grow the business mid-single digits for the fourth quarter. We expect to see solid gantry placements in Q4, continuing the steady performance we have delivered year-to-date. The demand for our portfolio of products and services remains strong, and we have solid visibility into gantry orders.
Further, our confidence in delivering more gantries than last year remains high. We are successfully managing resource availability among both our install teams and our customers, as customers balance the need to meet elevated demand for screening and staffing constraints. Finally, in Surgical, we anticipate Q4 revenue to grow mid-single digits. We expect the growth to continue come from MyoSure, Fluent, and our laparoscopy division, business.
Moving next to margins. Our guidance continues to assume a cadence of improvement moving into Q4, for both gross margin and operating margin. We remain on pace to exit the fiscal year in the low-60s for gross margin. Our guidance also assumes Q4 operating margins in the low-30s, and we are on pace to finish fiscal '24 between 30% to 31%, which includes the stub period of Endomagnetics.
Below operating income, we estimate fiscal '24 other income, net, to be an expense of approximately $8 million in Q4, and $11 million for the full year. Our guidance is based on an annual effective tax rate of approximately 19.75% and diluted shares outstanding are expected to be approximately 238 million for the full year.
To conclude, Q3 was another strong quarter for Hologic. We continue to deliver robust growth and quality earnings. As we approach the end of fiscal year 2024 and look ahead to 2025, we are excited by the performance across all our franchises and the additional strength provided by a pristine balance sheet. As always, our stakeholders can count on us to deliver while also advancing the state of women's health around the world.
With that, we ask the operator to open the call for questions.